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Find video protocols related to scientific articles indexed in Pubmed.
Concordance of genetic risk across migraine subgroups: Impact on current and future genetic association studies.
Cephalalgia
PUBLISHED: 09-01-2014
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There has been intensive debate whether migraine with aura (MA) and migraine without aura (MO) should be considered distinct subtypes or part of the same disease spectrum. There is also discussion to what extent migraine cases collected in specialised headache clinics differ from cases from population cohorts, and how female cases differ from male cases with respect to their migraine. To assess the genetic overlap between these migraine subgroups, we examined genome-wide association (GWA) results from analysis of 23,285 migraine cases and 95,425 population-matched controls.
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Defining the role of common variation in the genomic and biological architecture of adult human height.
Andrew R Wood, Tonu Esko, Jian Yang, Sailaja Vedantam, Tune H Pers, Stefan Gustafsson, Audrey Y Chu, Karol Estrada, Jian'an Luan, Zoltan Kutalik, Najaf Amin, Martin L Buchkovich, Damien C Croteau-Chonka, Felix R Day, Yanan Duan, Tove Fall, Rudolf Fehrmann, Teresa Ferreira, Anne U Jackson, Juha Karjalainen, Ken Sin Lo, Adam E Locke, Reedik Mägi, Evelin Mihailov, Eleonora Porcu, Joshua C Randall, André Scherag, Anna A E Vinkhuyzen, Harm-Jan Westra, Thomas W Winkler, Tsegaselassie Workalemahu, Jing Hua Zhao, Devin Absher, Eva Albrecht, Denise Anderson, Jeffrey Baron, Marian Beekman, Ayse Demirkan, Georg B Ehret, Bjarke Feenstra, Mary F Feitosa, Krista Fischer, Ross M Fraser, Anuj Goel, Jian Gong, Anne E Justice, Stavroula Kanoni, Marcus E Kleber, Kati Kristiansson, Unhee Lim, Vaneet Lotay, Julian C Lui, Massimo Mangino, Irene Mateo Leach, Carolina Medina-Gomez, Michael A Nalls, Dale R Nyholt, Cameron D Palmer, Dorota Pasko, Sonali Pechlivanis, Inga Prokopenko, Janina S Ried, Stephan Ripke, Dmitry Shungin, Alena Stančáková, Rona J Strawbridge, Yun Ju Sung, Toshiko Tanaka, Alexander Teumer, Stella Trompet, Sander W van der Laan, Jessica van Setten, Jana V van Vliet-Ostaptchouk, Zhaoming Wang, Loïc Yengo, Weihua Zhang, Uzma Afzal, Johan Arnlöv, Gillian M Arscott, Stefania Bandinelli, Amy Barrett, Claire Bellis, Amanda J Bennett, Christian Berne, Matthias Blüher, Jennifer L Bolton, Yvonne Böttcher, Heather A Boyd, Marcel Bruinenberg, Brendan M Buckley, Steven Buyske, Ida H Caspersen, Peter S Chines, Robert Clarke, Simone Claudi-Boehm, Matthew Cooper, E Warwick Daw, Pim A de Jong, Joris Deelen, Graciela Delgado, Josh C Denny, Rosalie Dhonukshe-Rutten, Maria Dimitriou, Alex S F Doney, Marcus Dörr, Niina Eklund, Elodie Eury, Lasse Folkersen, Melissa E Garcia, Frank Geller, Vilmantas Giedraitis, Alan S Go, Harald Grallert, Tanja B Grammer, Jürgen Gräßler, Henrik Grönberg, Lisette C P G M de Groot, Christopher J Groves, Jeffrey Haessler, Per Hall, Toomas Haller, Göran Hallmans, Anke Hannemann, Catharina A Hartman, Maija Hassinen, Caroline Hayward, Nancy L Heard-Costa, Quinta Helmer, Gibran Hemani, Anjali K Henders, Hans L Hillege, Mark A Hlatky, Wolfgang Hoffmann, Per Hoffmann, Oddgeir Holmen, Jeanine J Houwing-Duistermaat, Thomas Illig, Aaron Isaacs, Alan L James, Janina Jeff, Berit Johansen, Asa Johansson, Jennifer Jolley, Thorhildur Juliusdottir, Juhani Junttila, Abel N Kho, Leena Kinnunen, Norman Klopp, Thomas Kocher, Wolfgang Kratzer, Peter Lichtner, Lars Lind, Jaana Lindström, Stéphane Lobbens, Mattias Lorentzon, Yingchang Lu, Valeriya Lyssenko, Patrik K E Magnusson, Anubha Mahajan, Marc Maillard, Wendy L McArdle, Colin A McKenzie, Stela McLachlan, Paul J McLaren, Cristina Menni, Sigrun Merger, Lili Milani, Alireza Moayyeri, Keri L Monda, Mario A Morken, Gabriele Müller, Martina Müller-Nurasyid, Arthur W Musk, Narisu Narisu, Matthias Nauck, Ilja M Nolte, Markus M Nöthen, Laticia Oozageer, Stefan Pilz, Nigel W Rayner, Frida Renstrom, Neil R Robertson, Lynda M Rose, Ronan Roussel, Serena Sanna, Hubert Scharnagl, Salome Scholtens, Fredrick R Schumacher, Heribert Schunkert, Robert A Scott, Joban Sehmi, Thomas Seufferlein, Jianxin Shi, Karri Silventoinen, Johannes H Smit, Albert Vernon Smith, Joanna Smolonska, Alice V Stanton, Kathleen Stirrups, David J Stott, Heather M Stringham, Johan Sundström, Morris A Swertz, Ann-Christine Syvänen, Bamidele O Tayo, Gudmar Thorleifsson, Jonathan P Tyrer, Suzanne van Dijk, Natasja M van Schoor, Nathalie van der Velde, Diana van Heemst, Floor V A van Oort, Sita H Vermeulen, Niek Verweij, Judith M Vonk, Lindsay L Waite, Melanie Waldenberger, Roman Wennauer, Lynne R Wilkens, Christina Willenborg, Tom Wilsgaard, Mary K Wojczynski, Andrew Wong, Alan F Wright, Qunyuan Zhang, Dominique Arveiler, Stephan J L Bakker, John Beilby, Richard N Bergman, Sven Bergmann, Reiner Biffar, John Blangero, Dorret I Boomsma, Stefan R Bornstein, Pascal Bovet, Paolo Brambilla, Morris J Brown, Harry Campbell, Mark J Caulfield, Aravinda Chakravarti, Rory Collins, Francis S Collins, Dana C Crawford, L Adrienne Cupples, John Danesh, Ulf de Faire, Hester M den Ruijter, Raimund Erbel, Jeanette Erdmann, Johan G Eriksson, Martin Farrall, Ele Ferrannini, Jean Ferrières, Ian Ford, Nita G Forouhi, Terrence Forrester, Ron T Gansevoort, Pablo V Gejman, Christian Gieger, Alain Golay, Omri Gottesman, Vilmundur Gudnason, Ulf Gyllensten, David W Haas, Alistair S Hall, Tamara B Harris, Andrew T Hattersley, Andrew C Heath, Christian Hengstenberg, Andrew A Hicks, Lucia A Hindorff, Aroon D Hingorani, Albert Hofman, G Kees Hovingh, Steve E Humphries, Steven C Hunt, Elina Hyppönen, Kevin B Jacobs, Marjo-Riitta Järvelin, Pekka Jousilahti, Antti M Jula, Jaakko Kaprio, John J P Kastelein, Manfred Kayser, Frank Kee, Sirkka M Keinanen-Kiukaanniemi, Lambertus A Kiemeney, Jaspal S Kooner, Charles Kooperberg, Seppo Koskinen, Peter Kovacs, Aldi T Kraja, Meena Kumari, Johanna Kuusisto, Timo A Lakka, Claudia Langenberg, Loic Le Marchand, Terho Lehtimäki, Sara Lupoli, Pamela A F Madden, Satu Mannisto, Paolo Manunta, André Marette, Tara C Matise, Barbara McKnight, Thomas Meitinger, Frans L Moll, Grant W Montgomery, Andrew D Morris, Andrew P Morris, Jeffrey C Murray, Mari Nelis, Claes Ohlsson, Albertine J Oldehinkel, Ken K Ong, Willem H Ouwehand, Gerard Pasterkamp, Annette Peters, Peter P Pramstaller, Jackie F Price, Lu Qi, Olli T Raitakari, Tuomo Rankinen, D C Rao, Treva K Rice, Marylyn Ritchie, Igor Rudan, Veikko Salomaa, Nilesh J Samani, Jouko Saramies, Mark A Sarzynski, Peter E H Schwarz, Sylvain Sebert, Peter Sever, Alan R Shuldiner, Juha Sinisalo, Valgerdur Steinthorsdottir, Ronald P Stolk, Jean-Claude Tardif, Anke Tönjes, Angelo Tremblay, Elena Tremoli, Jarmo Virtamo, Marie-Claude Vohl, , Philippe Amouyel, Folkert W Asselbergs, Themistocles L Assimes, Murielle Bochud, Bernhard O Boehm, Eric Boerwinkle, Erwin P Bottinger, Claude Bouchard, Stéphane Cauchi, John C Chambers, Stephen J Chanock, Richard S Cooper, Paul I W de Bakker, George Dedoussis, Luigi Ferrucci, Paul W Franks, Philippe Froguel, Leif C Groop, Christopher A Haiman, Anders Hamsten, M Geoffrey Hayes, Jennie Hui, David J Hunter, Kristian Hveem, J Wouter Jukema, Robert C Kaplan, Mika Kivimäki, Diana Kuh, Markku Laakso, Yongmei Liu, Nicholas G Martin, Winfried März, Mads Melbye, Susanne Moebus, Patricia B Munroe, Inger Njølstad, Ben A Oostra, Colin N A Palmer, Nancy L Pedersen, Markus Perola, Louis Pérusse, Ulrike Peters, Joseph E Powell, Chris Power, Thomas Quertermous, Rainer Rauramaa, Eva Reinmaa, Paul M Ridker, Fernando Rivadeneira, Jerome I Rotter, Timo E Saaristo, Danish Saleheen, David Schlessinger, P Eline Slagboom, Harold Snieder, Tim D Spector, Konstantin Strauch, Michael Stumvoll, Jaakko Tuomilehto, Matti Uusitupa, Pim van der Harst, Henry Völzke, Mark Walker, Nicholas J Wareham, Hugh Watkins, H-Erich Wichmann, James F Wilson, Pieter Zanen, Panos Deloukas, Iris M Heid, Cecilia M Lindgren, Karen L Mohlke, Elizabeth K Speliotes, Unnur Thorsteinsdottir, Inês Barroso, Caroline S Fox, Kari E North, David P Strachan, Jacques S Beckmann, Sonja I Berndt, Michael Boehnke, Ingrid B Borecki, Mark I McCarthy, Andres Metspalu, Kari Stefansson, André G Uitterlinden, Cornelia M van Duijn, Lude Franke, Cristen J Willer, Alkes L Price, Guillaume Lettre, Ruth J F Loos, Michael N Weedon, Erik Ingelsson, Jeffrey R O'Connell, Gonçalo R Abecasis, Daniel I Chasman, Michael E Goddard, Peter M Visscher, Joel N Hirschhorn, Timothy M Frayling.
Nat. Genet.
PUBLISHED: 08-29-2014
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Using genome-wide data from 253,288 individuals, we identified 697 variants at genome-wide significance that together explained one-fifth of the heritability for adult height. By testing different numbers of variants in independent studies, we show that the most strongly associated ?2,000, ?3,700 and ?9,500 SNPs explained ?21%, ?24% and ?29% of phenotypic variance. Furthermore, all common variants together captured 60% of heritability. The 697 variants clustered in 423 loci were enriched for genes, pathways and tissue types known to be involved in growth and together implicated genes and pathways not highlighted in earlier efforts, such as signaling by fibroblast growth factors, WNT/?-catenin and chondroitin sulfate-related genes. We identified several genes and pathways not previously connected with human skeletal growth, including mTOR, osteoglycin and binding of hyaluronic acid. Our results indicate a genetic architecture for human height that is characterized by a very large but finite number (thousands) of causal variants.
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Mutations in APOPT1, encoding a mitochondrial protein, cause cavitating leukoencephalopathy with cytochrome c oxidase deficiency.
Am. J. Hum. Genet.
PUBLISHED: 08-28-2014
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Cytochrome c oxidase (COX) deficiency is a frequent biochemical abnormality in mitochondrial disorders, but a large fraction of cases remains genetically undetermined. Whole-exome sequencing led to the identification of APOPT1 mutations in two Italian sisters and in a third Turkish individual presenting severe COX deficiency. All three subjects presented a distinctive brain MRI pattern characterized by cavitating leukodystrophy, predominantly in the posterior region of the cerebral hemispheres. We then found APOPT1 mutations in three additional unrelated children, selected on the basis of these particular MRI features. All identified mutations predicted the synthesis of severely damaged protein variants. The clinical features of the six subjects varied widely from acute neurometabolic decompensation in late infancy to subtle neurological signs, which appeared in adolescence; all presented a chronic, long-surviving clinical course. We showed that APOPT1 is targeted to and localized within mitochondria by an N-terminal mitochondrial targeting sequence that is eventually cleaved off from the mature protein. We then showed that APOPT1 is virtually absent in fibroblasts cultured in standard conditions, but its levels increase by inhibiting the proteasome or after oxidative challenge. Mutant fibroblasts showed reduced amount of COX holocomplex and higher levels of reactive oxygen species, which both shifted toward control values by expressing a recombinant, wild-type APOPT1 cDNA. The shRNA-mediated knockdown of APOPT1 in myoblasts and fibroblasts caused dramatic decrease in cell viability. APOPT1 mutations are responsible for infantile or childhood-onset mitochondrial disease, hallmarked by the combination of profound COX deficiency with a distinctive neuroimaging presentation.
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Mitochondrial genetic variants identified to be associated with BMI in adults.
PLoS ONE
PUBLISHED: 08-25-2014
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It has been suggested that mitochondrial dysfunction plays a role in metabolic disorders including obesity, diabetes, and hypertension. The fact that mitochondrial defects can be accumulated over time as a normal part of aging may explain why some individuals can eat all sorts of foods and remain at normal weight while they are young. However, around the fourth decade of life there is a trend towards "middle-age spread" with weight gain and the body's decreasing ability to metabolize calories efficiently. To test the hypothesis that mitochondrial variants are associated with BMI in adults, we analyzed a total number of 984 mitochondrial single nucleotide polymorphisms (mtSNPs) in a sample of 6,528 individuals participating in the KORA studies. To assess mtSNP association while taking heteroplasmy into account we used the raw signal intensity values measured on the microarray and applied linear regression. Significant results were obtained for 2 mtSNPs located in the Cytochrome c oxidase subunit genes (MT-CO1: Padjusted?=?0.0140 and MT-CO3: Padjusted?=?0.0286) and 3 mtSNPs located in the NADH dehydrogenase subunit genes (MT-ND1, MT-ND2 and MT-ND4L: Padjusted?=?0.0286). Polymorphisms located in the MT-CO3 and MT-ND4L genes have not been associated with BMI or related phenotypes in the past. Our results highlight the importance of the mitochondrial genome among the factors that contribute to the risk of high BMI. Focusing on mitochondrial variants may lead to further insights regarding effects of existing medications, or even to the development of innovative treatments.
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DYT16 revisited: exome sequencing identifies PRKRA mutations in a European dystonia family.
Mov. Disord.
PUBLISHED: 08-20-2014
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Recessive DYT16 dystonia associated with mutations in PRKRA has until now been reported only in seven Brazilian patients. The aim of this study was to elucidate the genetic cause underlying disease in a Polish family with autosomal-recessive, early-onset generalized dystonia and slight parkinsonism, and to explore further the role of PRKRA in a dystonia series of European ancestry. We employed whole-exome sequencing in two affected siblings of the Polish family and filtered for rare homozygous and compound heterozygous variants shared by both exomes. Validation of the identified variants as well as homozygosity screening and copy number variation analysis was carried out in the two affected individuals and their healthy siblings. PRKRA was analyzed in 339 German patients with various forms of dystonia and 376 population-based controls by direct sequencing or high-resolution melting. The previously described homozygous p.Pro222Leu mutation in PRKRA was found to segregate with the disease in the studied family, contained in a 1.2 Mb homozygous region identical by state with all Brazilian patients in chromosome 2q31.2. The clinical presentation with young-onset, progressive generalized dystonia and mild parkinsonism resembled the phenotype of the original DYT16 cases. PRKRA mutational screening in additional dystonia samples revealed three novel heterozygous changes (p.Thr34Ser, p.Asn102Ser, c.-14A>G), each in a single subject with focal/segmental dystonia. Our study provides the first independent replication of the DYT16 locus at 2q31.2 and strongly confirms the causal contribution of the PRKRA gene to DYT16. Our data suggest worldwide involvement of PRKRA in dystonia.
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Loss-of-function mutations in APOC3, triglycerides, and coronary disease.
N. Engl. J. Med.
PUBLISHED: 06-18-2014
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Plasma triglyceride levels are heritable and are correlated with the risk of coronary heart disease. Sequencing of the protein-coding regions of the human genome (the exome) has the potential to identify rare mutations that have a large effect on phenotype.
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A powerful tool for genome analysis in maize: development and evaluation of the high density 600 k SNP genotyping array.
BMC Genomics
PUBLISHED: 06-11-2014
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High density genotyping data are indispensable for genomic analyses of complex traits in animal and crop species. Maize is one of the most important crop plants worldwide, however a high density SNP genotyping array for analysis of its large and highly dynamic genome was not available so far.
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Targeted resequencing and systematic in vivo functional testing identifies rare variants in MEIS1 as significant contributors to restless legs syndrome.
Am. J. Hum. Genet.
PUBLISHED: 06-10-2014
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Restless legs syndrome (RLS) is a common neurologic condition characterized by nocturnal dysesthesias and an urge to move, affecting the legs. RLS is a complex trait, for which genome-wide association studies (GWASs) have identified common susceptibility alleles of modest (OR 1.2-1.7) risk at six genomic loci. Among these, variants in MEIS1 have emerged as the largest risk factors for RLS, suggesting that perturbations in this transcription factor might be causally related to RLS susceptibility. To establish this causality, direction of effect, and total genetic burden of MEIS1, we interrogated 188 case subjects and 182 control subjects for rare alleles not captured by previous GWASs, followed by genotyping of ?3,000 case subjects and 3,000 control subjects, and concluded with systematic functionalization of all discovered variants using a previously established in vivo model of neurogenesis. We observed a significant excess of rare MEIS1 variants in individuals with RLS. Subsequent assessment of all nonsynonymous variants by in vivo complementation revealed an excess of loss-of-function alleles in individuals with RLS. Strikingly, these alleles compromised the function of the canonical MEIS1 splice isoform but were irrelevant to an isoform known to utilize an alternative 3' sequence. Our data link MEIS1 loss of function to the etiopathology of RLS, highlight how combined sequencing and systematic functional annotation of rare variation at GWAS loci can detect risk burden, and offer a plausible explanation for the specificity of phenotypic expressivity of loss-of-function alleles at a locus broadly necessary for neurogenesis and neurodevelopment.
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Novel calmodulin mutations associated with congenital arrhythmia susceptibility.
Circ Cardiovasc Genet
PUBLISHED: 06-10-2014
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Genetic predisposition to life-threatening cardiac arrhythmias such as congenital long-QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT) represent treatable causes of sudden cardiac death in young adults and children. Recently, mutations in calmodulin (CALM1, CALM2) have been associated with severe forms of LQTS and CPVT, with life-threatening arrhythmias occurring very early in life. Additional mutation-positive cases are needed to discern genotype-phenotype correlations associated with calmodulin mutations.
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Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.
Dan E Arking, Sara L Pulit, Lia Crotti, Pim van der Harst, Patricia B Munroe, Tamara T Koopmann, Nona Sotoodehnia, Elizabeth J Rossin, Michael Morley, Xinchen Wang, Andrew D Johnson, Alicia Lundby, Daniel F Gudbjartsson, Peter A Noseworthy, Mark Eijgelsheim, Yuki Bradford, Kirill V Tarasov, Marcus Dörr, Martina Müller-Nurasyid, Annukka M Lahtinen, Ilja M Nolte, Albert Vernon Smith, Joshua C Bis, Aaron Isaacs, Stephen J Newhouse, Daniel S Evans, Wendy S Post, Daryl Waggott, Leo-Pekka Lyytikäinen, Andrew A Hicks, Lewin Eisele, David Ellinghaus, Caroline Hayward, Pau Navarro, Sheila Ulivi, Toshiko Tanaka, David J Tester, Stéphanie Chatel, Stefan Gustafsson, Meena Kumari, Richard W Morris, Asa T Naluai, Sandosh Padmanabhan, Alexander Kluttig, Bernhard Strohmer, Andrie G Panayiotou, Maria Torres, Michael Knoflach, Jaroslav A Hubacek, Kamil Slowikowski, Soumya Raychaudhuri, Runjun D Kumar, Tamara B Harris, Lenore J Launer, Alan R Shuldiner, Alvaro Alonso, Joel S Bader, Georg Ehret, Hailiang Huang, W H Linda Kao, James B Strait, Peter W Macfarlane, Morris Brown, Mark J Caulfield, Nilesh J Samani, Florian Kronenberg, Johann Willeit, , J Gustav Smith, Karin H Greiser, Henriette Meyer zu Schwabedissen, Karl Werdan, Massimo Carella, Leopoldo Zelante, Susan R Heckbert, Bruce M Psaty, Jerome I Rotter, Ivana Kolčić, Ozren Polašek, Alan F Wright, Maura Griffin, Mark J Daly, David O Arnar, Hilma Holm, Unnur Thorsteinsdottir, Joshua C Denny, Dan M Roden, Rebecca L Zuvich, Valur Emilsson, Andrew S Plump, Martin G Larson, Christopher J O'Donnell, Xiaoyan Yin, Marco Bobbo, Adamo P d'Adamo, AnnaMaria Iorio, Gianfranco Sinagra, Angel Carracedo, Steven R Cummings, Michael A Nalls, Antti Jula, Kimmo K Kontula, Annukka Marjamaa, Lasse Oikarinen, Markus Perola, Kimmo Porthan, Raimund Erbel, Per Hoffmann, Karl-Heinz Jöckel, Hagen Kälsch, Markus M Nöthen, Marcel den Hoed, Ruth J F Loos, Dag S Thelle, Christian Gieger, Thomas Meitinger, Siegfried Perz, Annette Peters, Hanna Prucha, Moritz F Sinner, Melanie Waldenberger, Rudolf A de Boer, Lude Franke, Pieter A van der Vleuten, Britt Maria Beckmann, Eimo Martens, Abdennasser Bardai, Nynke Hofman, Arthur A M Wilde, Elijah R Behr, Chrysoula Dalageorgou, John R Giudicessi, Argelia Medeiros-Domingo, Julien Barc, Florence Kyndt, Vincent Probst, Alice Ghidoni, Roberto Insolia, Robert M Hamilton, Stephen W Scherer, Jeffrey Brandimarto, Kenneth Margulies, Christine E Moravec, Fabiola Del Greco M, Christian Fuchsberger, Jeffrey R O'Connell, Wai K Lee, Graham C M Watt, Harry Campbell, Sarah H Wild, Nour E El Mokhtari, Norbert Frey, Folkert W Asselbergs, Irene Mateo Leach, Gerjan Navis, Maarten P van den Berg, Dirk J van Veldhuisen, Manolis Kellis, Bouwe P Krijthe, Oscar H Franco, Albert Hofman, Jan A Kors, André G Uitterlinden, Jacqueline C M Witteman, Lyudmyla Kedenko, Claudia Lamina, Ben A Oostra, Gonçalo R Abecasis, Edward G Lakatta, Antonella Mulas, Marco Orrù, David Schlessinger, Manuela Uda, Marcello R P Markus, Uwe Völker, Harold Snieder, Timothy D Spector, Johan Arnlöv, Lars Lind, Johan Sundström, Ann-Christine Syvänen, Mika Kivimäki, Mika Kähönen, Nina Mononen, Olli T Raitakari, Jorma S Viikari, Vera Adamkova, Stefan Kiechl, María Brión, Andrew N Nicolaides, Bernhard Paulweber, Johannes Haerting, Anna F Dominiczak, Fredrik Nyberg, Peter H Whincup, Aroon D Hingorani, Jean-Jacques Schott, Connie R Bezzina, Erik Ingelsson, Luigi Ferrucci, Paolo Gasparini, James F Wilson, Igor Rudan, Andre Franke, Thomas W Mühleisen, Peter P Pramstaller, Terho J Lehtimäki, Andrew D Paterson, Afshin Parsa, Yongmei Liu, Cornelia M van Duijn, David S Siscovick, Vilmundur Gudnason, Yalda Jamshidi, Veikko Salomaa, Stephan B Felix, Serena Sanna, Marylyn D Ritchie, Bruno H Stricker, Kari Stefansson, Laurie A Boyer, Thomas P Cappola, Jesper V Olsen, Kasper Lage, Peter J Schwartz, Stefan Kääb, Aravinda Chakravarti, Michael J Ackerman, Arne Pfeufer, Paul I W de Bakker, Christopher Newton-Cheh.
Nat. Genet.
PUBLISHED: 05-29-2014
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The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ?8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.
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Novel (ovario) leukodystrophy related to AARS2 mutations.
Neurology
PUBLISHED: 05-07-2014
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The study was focused on leukoencephalopathies of unknown cause in order to define a novel, homogeneous phenotype suggestive of a common genetic defect, based on clinical and MRI findings, and to identify the causal genetic defect shared by patients with this phenotype.
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Novel loci affecting iron homeostasis and their effects in individuals at risk for hemochromatosis.
Nat Commun
PUBLISHED: 05-01-2014
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Variation in body iron is associated with or causes diseases, including anaemia and iron overload. Here, we analyse genetic association data on biochemical markers of iron status from 11 European-population studies, with replication in eight additional cohorts (total up to 48,972 subjects). We find 11 genome-wide-significant (P<5 × 10(-8)) loci, some including known iron-related genes (HFE, SLC40A1, TF, TFR2, TFRC, TMPRSS6) and others novel (ABO, ARNTL, FADS2, NAT2, TEX14). SNPs at ARNTL, TF, and TFR2 affect iron markers in HFE C282Y homozygotes at risk for hemochromatosis. There is substantial overlap between our iron loci and loci affecting erythrocyte and lipid phenotypes. These results will facilitate investigation of the roles of iron in disease.
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VARS2 and TARS2 mutations in patients with mitochondrial encephalomyopathies.
Hum. Mutat.
PUBLISHED: 04-29-2014
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By way of whole-exome sequencing, we identified a homozygous missense mutation in VARS2 in one subject with microcephaly and epilepsy associated with isolated deficiency of the mitochondrial respiratory chain (MRC) complex I and compound heterozygous mutations in TARS2 in two siblings presenting with axial hypotonia and severe psychomotor delay associated with multiple MRC defects. The nucleotide variants segregated within the families, were absent in Single Nucleotide Polymorphism (SNP) databases and are predicted to be deleterious. The amount of VARS2 and TARS2 proteins and valyl-tRNA and threonyl-tRNA levels were decreased in samples of afflicted patients according to the genetic defect. Expression of the corresponding wild-type transcripts in immortalized mutant fibroblasts rescued the biochemical impairment of mitochondrial respiration and yeast modeling of the VARS2 mutation confirmed its pathogenic role. Taken together, these data demonstrate the role of the identified mutations for these mitochondriopathies. Our study reports the first mutations in the VARS2 and TARS2 genes, which encode two mitochondrial aminoacyl-tRNA synthetases, as causes of clinically distinct, early-onset mitochondrial encephalopathies.
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Genome-wide association study for refractive astigmatism reveals genetic co-determination with spherical equivalent refractive error: the CREAM consortium.
Hum. Genet.
PUBLISHED: 04-14-2014
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To identify genetic variants associated with refractive astigmatism in the general population, meta-analyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295); White Europeans aged <25 years (4 cohorts, N = 5,640); and all independent individuals from the above three samples combined with a sample of Chinese subjects aged <25 years (N = 45,931). Participants were classified as cases with refractive astigmatism if the average cylinder power in their two eyes was at least 1.00 diopter and as controls otherwise. Genome-wide association analysis was carried out for each cohort separately using logistic regression. Meta-analysis was conducted using a fixed effects model. In the older European group the most strongly associated marker was downstream of the neurexin-1 (NRXN1) gene (rs1401327, P = 3.92E-8). No other region reached genome-wide significance, and association signals were lower for the younger European group and Asian group. In the meta-analysis of all cohorts, no marker reached genome-wide significance: The most strongly associated regions were, NRXN1 (rs1401327, P = 2.93E-07), TOX (rs7823467, P = 3.47E-07) and LINC00340 (rs12212674, P = 1.49E-06). For 34 markers identified in prior GWAS for spherical equivalent refractive error, the beta coefficients for genotype versus spherical equivalent, and genotype versus refractive astigmatism, were highly correlated (r = -0.59, P = 2.10E-04). This work revealed no consistent or strong genetic signals for refractive astigmatism; however, the TOX gene region previously identified in GWAS for spherical equivalent refractive error was the second most strongly associated region. Analysis of additional markers provided evidence supporting widespread genetic co-susceptibility for spherical and astigmatic refractive errors.
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Restless legs syndrome-associated intronic common variant in Meis1 alters enhancer function in the developing telencephalon.
Genome Res.
PUBLISHED: 03-18-2014
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Genome-wide association studies (GWAS) identified the MEIS1 locus for Restless Legs Syndrome (RLS), but causal single nucleotide polymorphisms (SNPs) and their functional relevance remain unknown. This locus contains a large number of highly conserved noncoding regions (HCNRs) potentially functioning as cis-regulatory modules. We analyzed these HCNRs for allele-dependent enhancer activity in zebrafish and mice and found that the risk allele of the lead SNP rs12469063 reduces enhancer activity in the Meis1 expression domain of the murine embryonic ganglionic eminences (GE). CREB1 binds this enhancer and rs12469063 affects its binding in vitro. In addition, MEIS1 target genes suggest a role in the specification of neuronal progenitors in the GE, and heterozygous Meis1-deficient mice exhibit hyperactivity, resembling the RLS phenotype. Thus, in vivo and in vitro analysis of a common SNP with small effect size showed allele-dependent function in the prospective basal ganglia representing the first neurodevelopmental region implicated in RLS.
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Genome-wide genotyping demonstrates a polygenic risk score associated with white matter hyperintensity volume in CADASIL.
Stroke
PUBLISHED: 02-27-2014
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White matter hyperintensities (WMH) on MRI are a quantitative marker for sporadic cerebral small vessel disease and are highly heritable. To date, large-scale genetic studies have identified only a single locus influencing WMH burden. This might in part relate to biological heterogeneity of sporadic WMH. The current study searched for genetic modifiers of WMH volume in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a monogenic small vessel disease.
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Loss-of-function mutations in SLC30A8 protect against type 2 diabetes.
Nat. Genet.
PUBLISHED: 02-10-2014
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Loss-of-function mutations protective against human disease provide in vivo validation of therapeutic targets, but none have yet been described for type 2 diabetes (T2D). Through sequencing or genotyping of ~150,000 individuals across 5 ancestry groups, we identified 12 rare protein-truncating variants in SLC30A8, which encodes an islet zinc transporter (ZnT8) and harbors a common variant (p.Trp325Arg) associated with T2D risk and glucose and proinsulin levels. Collectively, carriers of protein-truncating variants had 65% reduced T2D risk (P = 1.7 × 10(-6)), and non-diabetic Icelandic carriers of a frameshift variant (p.Lys34Serfs*50) demonstrated reduced glucose levels (-0.17 s.d., P = 4.6 × 10(-4)). The two most common protein-truncating variants (p.Arg138* and p.Lys34Serfs*50) individually associate with T2D protection and encode unstable ZnT8 proteins. Previous functional study of SLC30A8 suggested that reduced zinc transport increases T2D risk, and phenotypic heterogeneity was observed in mouse Slc30a8 knockouts. In contrast, loss-of-function mutations in humans provide strong evidence that SLC30A8 haploinsufficiency protects against T2D, suggesting ZnT8 inhibition as a therapeutic strategy in T2D prevention.
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Phenotypic spectrum of eleven patients and five novel MTFMT mutations identified by exome sequencing and candidate gene screening.
Mol. Genet. Metab.
PUBLISHED: 01-28-2014
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Defects of mitochondrial oxidative phosphorylation (OXPHOS) are associated with a wide range of clinical phenotypes and time courses. Combined OXPHOS deficiencies are mainly caused by mutations of nuclear genes that are involved in mitochondrial protein translation. Due to their genetic heterogeneity it is almost impossible to diagnose OXPHOS patients on clinical grounds alone. Hence next generation sequencing (NGS) provides a distinct advantage over candidate gene sequencing to discover the underlying genetic defect in a timely manner. One recent example is the identification of mutations in MTFMT that impair mitochondrial protein translation through decreased formylation of Met-tRNA(Met). Here we report the results of a combined exome sequencing and candidate gene screening study. We identified nine additional MTFMT patients from eight families who were affected with Leigh encephalopathy or white matter disease, microcephaly, mental retardation, ataxia, and muscular hypotonia. In four patients, the causal mutations were identified by exome sequencing followed by stringent bioinformatic filtering. In one index case, exome sequencing identified a single heterozygous mutation leading to Sanger sequencing which identified a second mutation in the non-covered first exon. High-resolution melting curve-based MTFMT screening in 350 OXPHPOS patients identified pathogenic mutations in another three index cases. Mutations in one of them were not covered by previous exome sequencing. All novel mutations predict a loss-of-function or result in a severe decrease in MTFMT protein in patients' fibroblasts accompanied by reduced steady-state levels of complex I and IV subunits. Being present in 11 out of 13 index cases the c.626C>T mutation is one of the most frequent disease alleles underlying OXPHOS disorders. We provide detailed clinical descriptions on eleven MTFMT patients and review five previously reported cases.
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Whole-exome sequencing identifies rare and low-frequency coding variants associated with LDL cholesterol.
Leslie A Lange, Youna Hu, He Zhang, Chenyi Xue, Ellen M Schmidt, Zheng-zheng Tang, Chris Bizon, Ethan M Lange, Joshua D Smith, Emily H Turner, Goo Jun, Hyun Min Kang, Gina Peloso, Paul Auer, Kuo-Ping Li, Jason Flannick, Ji Zhang, Christian Fuchsberger, Kyle Gaulton, Cecilia Lindgren, Adam Locke, Alisa Manning, Xueling Sim, Manuel A Rivas, Oddgeir L Holmen, Omri Gottesman, Yingchang Lu, Douglas Ruderfer, Eli A Stahl, Qing Duan, Yun Li, Peter Durda, Shuo Jiao, Aaron Isaacs, Albert Hofman, Joshua C Bis, Adolfo Correa, Michael E Griswold, Johanna Jakobsdottir, Albert V Smith, Pamela J Schreiner, Mary F Feitosa, Qunyuan Zhang, Jennifer E Huffman, Jacy Crosby, Christina L Wassel, Ron Do, Nora Franceschini, Lisa W Martin, Jennifer G Robinson, Themistocles L Assimes, David R Crosslin, Elisabeth A Rosenthal, Michael Tsai, Mark J Rieder, Deborah N Farlow, Aaron R Folsom, Thomas Lumley, Ervin R Fox, Christopher S Carlson, Ulrike Peters, Rebecca D Jackson, Cornelia M van Duijn, André G Uitterlinden, Daniel Levy, Jerome I Rotter, Herman A Taylor, Vilmundur Gudnason, David S Siscovick, Myriam Fornage, Ingrid B Borecki, Caroline Hayward, Igor Rudan, Y Eugene Chen, Erwin P Bottinger, Ruth J F Loos, Pål Sætrom, Kristian Hveem, Michael Boehnke, Leif Groop, Mark McCarthy, Thomas Meitinger, Christie M Ballantyne, Stacey B Gabriel, Christopher J O'Donnell, Wendy S Post, Kari E North, Alexander P Reiner, Eric Boerwinkle, Bruce M Psaty, David Altshuler, Sekar Kathiresan, Dan-Yu Lin, Gail P Jarvik, L Adrienne Cupples, Charles Kooperberg, James G Wilson, Deborah A Nickerson, Gonçalo R Abecasis, Stephen S Rich, Russell P Tracy, Cristen J Willer, .
Am. J. Hum. Genet.
PUBLISHED: 01-14-2014
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Elevated low-density lipoprotein cholesterol (LDL-C) is a treatable, heritable risk factor for cardiovascular disease. Genome-wide association studies (GWASs) have identified 157 variants associated with lipid levels but are not well suited to assess the impact of rare and low-frequency variants. To determine whether rare or low-frequency coding variants are associated with LDL-C, we exome sequenced 2,005 individuals, including 554 individuals selected for extreme LDL-C (>98(th) or <2(nd) percentile). Follow-up analyses included sequencing of 1,302 additional individuals and genotype-based analysis of 52,221 individuals. We observed significant evidence of association between LDL-C and the burden of rare or low-frequency variants in PNPLA5, encoding a phospholipase-domain-containing protein, and both known and previously unidentified variants in PCSK9, LDLR and APOB, three known lipid-related genes. The effect sizes for the burden of rare variants for each associated gene were substantially higher than those observed for individual SNPs identified from GWASs. We replicated the PNPLA5 signal in an independent large-scale sequencing study of 2,084 individuals. In conclusion, this large whole-exome-sequencing study for LDL-C identified a gene not known to be implicated in LDL-C and provides unique insight into the design and analysis of similar experiments.
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Genome-wide meta-analysis of myopia and hyperopia provides evidence for replication of 11 loci.
PLoS ONE
PUBLISHED: 01-01-2014
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Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p?=?1.25×10(-8)), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value?=?9.11×10(-11)) and 8q12 (minimum p value 1.82×10(-11)) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. "Replication-level" association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.
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A systematic evaluation of short tandem repeats in lipid candidate genes: riding on the SNP-wave.
PLoS ONE
PUBLISHED: 01-01-2014
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Structural genetic variants as short tandem repeats (STRs) are not targeted in SNP-based association studies and thus, their possible association signals are missed. We systematically searched for STRs in gene regions known to contribute to total cholesterol, HDL cholesterol, LDL cholesterol and triglyceride levels in two independent studies (KORA F4, n?=?2553 and SAPHIR, n?=?1648), resulting in 16 STRs that were finally evaluated. In a combined dataset of both studies, the sum of STR alleles was regressed on each phenotype, adjusted for age and sex. The association analyses were repeated for SNPs in a 200 kb region surrounding the respective STRs in the KORA F4 Study. Three STRs were significantly associated with total cholesterol (within LDLR, the APOA1/C3/A4/A5/BUD13 gene region and ABCG5/8), five with HDL cholesterol (3 within CETP, one in LPL and one inAPOA1/C3/A4/A5/BUD13), three with LDL cholesterol (LDLR, ABCG5/8 and CETP) and two with triglycerides (APOA1/C3/A4/A5/BUD13 and LPL). None of the investigated STRs, however, showed a significant association after adjusting for the lead or adjacent SNPs within that gene region. The evaluated STRs were found to be well tagged by the lead SNP within the respective gene regions. Therefore, the STRs reflect the association signals based on surrounding SNPs. In conclusion, none of the STRs contributed additionally to the SNP-based association signals identified in GWAS on lipid traits.
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Blood cis-eQTL analysis fails to identify novel association signals among sub-threshold candidates from genome-wide association studies in restless legs syndrome.
PLoS ONE
PUBLISHED: 01-01-2014
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Restless legs syndrome (RLS) is a common neurologic disorder characterized by nightly dysesthesias affecting the legs primarily during periods of rest and relieved by movement. RLS is a complex genetic disease and susceptibility factors in six genomic regions have been identified by means of genome-wide association studies (GWAS). For some complex genetic traits, expression quantitative trait loci (eQTLs) are enriched among trait-associated single nucleotide polymorphisms (SNPs). With the aim of identifying new genetic susceptibility factors for RLS, we assessed the 332 best-associated SNPs from the genome-wide phase of the to date largest RLS GWAS for cis-eQTL effects in peripheral blood from individuals of European descent. In 740 individuals belonging to the KORA general population cohort, 52 cis-eQTLs with pnominal<10(-3) were identified, while in 976 individuals belonging to the SHIP-TREND general population study 53 cis-eQTLs with pnominal<10(-3) were present. 23 of these cis-eQTLs overlapped between the two cohorts. Subsequently, the twelve of the 23 cis-eQTL SNPs, which were not located at an already published RLS-associated locus, were tested for association in 2449 RLS cases and 1462 controls. The top SNP, located in the DET1 gene, was nominally significant (p<0.05) but did not withstand correction for multiple testing (p?=?0.42). Although a similar approach has been used successfully with regard to other complex diseases, we were unable to identify new genetic susceptibility factor for RLS by adding this novel level of functional assessment to RLS GWAS data.
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Impairment of Drosophila orthologs of the human orphan protein C19orf12 induces bang sensitivity and neurodegeneration.
PLoS ONE
PUBLISHED: 01-01-2014
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Mutations in the orphan gene C19orf12 were identified as a genetic cause in a subgroup of patients with NBIA, a neurodegenerative disorder characterized by deposits of iron in the basal ganglia. C19orf12 was shown to be localized in mitochondria, however, nothing is known about its activity and no functional link exists to the clinical phenotype of the patients. This situation led us to investigate the effects of C19orf12 down-regulation in the model organism Drosophila melanogaster. Two genes are present in D. melanogaster, which are orthologs of C19orf12, CG3740 and CG11671. Here we provide evidence that transgenic flies with impaired C19orf12 homologs reflect the neurodegenerative phenotype and represent a valid tool to further analyze the pathomechanism in C19orf12-associated NBIA.
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Mitochondrial membrane protein-associated neurodegeneration (MPAN).
Int. Rev. Neurobiol.
PUBLISHED: 11-12-2013
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Neurodegeneration with brain iron accumulation (NBIA) is a group of rare and devastating disorders characterized by iron deposition in the brain. Mutations in C19orf12 cause autosomal recessive inherited mitochondrial membrane protein-associated neurodegeneration (MPAN), which may account for up to 30% of NBIA cases. The C19orf12 gene product is an orphan mitochondrial membrane protein, and most mutations are predicted to cause loss of function. From 67 MPAN cases so far reported, we describe here the clinical, radiological, and genetic features. Key clinical features are pyramidal and extrapyramidal signs, cognitive decline, neuropsychiatric abnormalities, optic atrophy, and motor axonal neuropathy. Magnetic resonance imaging shows the eponymous brain iron accumulation in globus pallidus and substantia nigra and in some cases a hyperintense streaking of the medial medullary lamina. The latter sign may discriminate MPAN from other NBIA subtypes. In two postmortem MPAN cases, neuropathology showed axonal spheroids, Lewy bodies, and hyperphosphorylated tau-containing inclusions.
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Dysfunctional nitric oxide signalling increases risk of myocardial infarction.
Nature
PUBLISHED: 09-27-2013
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Myocardial infarction, a leading cause of death in the Western world, usually occurs when the fibrous cap overlying an atherosclerotic plaque in a coronary artery ruptures. The resulting exposure of blood to the atherosclerotic material then triggers thrombus formation, which occludes the artery. The importance of genetic predisposition to coronary artery disease and myocardial infarction is best documented by the predictive value of a positive family history. Next-generation sequencing in families with several affected individuals has revolutionized mutation identification. Here we report the segregation of two private, heterozygous mutations in two functionally related genes, GUCY1A3 (p.Leu163Phefs*24) and CCT7 (p.Ser525Leu), in an extended myocardial infarction family. GUCY1A3 encodes the ?1 subunit of soluble guanylyl cyclase (?1-sGC), and CCT7 encodes CCT?, a member of the tailless complex polypeptide 1 ring complex, which, among other functions, stabilizes soluble guanylyl cyclase. After stimulation with nitric oxide, soluble guanylyl cyclase generates cGMP, which induces vasodilation and inhibits platelet activation. We demonstrate in vitro that mutations in both GUCY1A3 and CCT7 severely reduce ?1-sGC as well as ?1-sGC protein content, and impair soluble guanylyl cyclase activity. Moreover, platelets from digenic mutation carriers contained less soluble guanylyl cyclase protein and consequently displayed reduced nitric-oxide-induced cGMP formation. Mice deficient in ?1-sGC protein displayed accelerated thrombus formation in the microcirculation after local trauma. Starting with a severely affected family, we have identified a link between impaired soluble-guanylyl-cyclase-dependent nitric oxide signalling and myocardial infarction risk, possibly through accelerated thrombus formation. Reversing this defect may provide a new therapeutic target for reducing the risk of myocardial infarction.
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Meta-analysis of genome-wide association studies identifies six new Loci for serum calcium concentrations.
Conall M O'Seaghdha, Hongsheng Wu, Qiong Yang, Karen Kapur, Idris Guessous, Annie Mercier Zuber, Anna Köttgen, Candice Stoudmann, Alexander Teumer, Zoltan Kutalik, Massimo Mangino, Abbas Dehghan, Weihua Zhang, Gudny Eiriksdottir, Guo Li, Toshiko Tanaka, Laura Portas, Lorna M Lopez, Caroline Hayward, Kurt Lohman, Koichi Matsuda, Sandosh Padmanabhan, Dmitri Firsov, Rossella Sorice, Sheila Ulivi, A Catharina Brockhaus, Marcus E Kleber, Anubha Mahajan, Florian D Ernst, Vilmundur Gudnason, Lenore J Launer, Aurelien Macé, Eric Boerwinckle, Dan E Arking, Chizu Tanikawa, Yusuke Nakamura, Morris J Brown, Jean-Michel Gaspoz, Jean-Marc Theler, David S Siscovick, Bruce M Psaty, Sven Bergmann, Peter Vollenweider, Veronique Vitart, Alan F Wright, Tatijana Zemunik, Mladen Boban, Ivana Kolčić, Pau Navarro, Edward M Brown, Karol Estrada, Jingzhong Ding, Tamara B Harris, Stefania Bandinelli, Dena Hernandez, Andrew B Singleton, Giorgia Girotto, Daniela Ruggiero, Adamo Pio D'adamo, Antonietta Robino, Thomas Meitinger, Christa Meisinger, Gail Davies, John M Starr, John C Chambers, Bernhard O Boehm, Bernhard R Winkelmann, Jie Huang, Federico Murgia, Sarah H Wild, Harry Campbell, Andrew P Morris, Oscar H Franco, Albert Hofman, André G Uitterlinden, Fernando Rivadeneira, Uwe Völker, Anke Hannemann, Reiner Biffar, Wolfgang Hoffmann, So-Youn Shin, Pierre Lescuyer, Hughes Henry, Claudia Schurmann, , Patricia B Munroe, Paolo Gasparini, Nicola Pirastu, Marina Ciullo, Christian Gieger, Winfried März, Lars Lind, Tim D Spector, Albert V Smith, Igor Rudan, James F Wilson, Ozren Polašek, Ian J Deary, Mario Pirastu, Luigi Ferrucci, Yongmei Liu, Bryan Kestenbaum, Jaspal S Kooner, Jacqueline C M Witteman, Matthias Nauck, W H Linda Kao, Henri Wallaschofski, Olivier Bonny, Caroline S Fox, Murielle Bochud.
PLoS Genet.
PUBLISHED: 09-01-2013
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Calcium is vital to the normal functioning of multiple organ systems and its serum concentration is tightly regulated. Apart from CASR, the genes associated with serum calcium are largely unknown. We conducted a genome-wide association meta-analysis of 39,400 individuals from 17 population-based cohorts and investigated the 14 most strongly associated loci in ? 21,679 additional individuals. Seven loci (six new regions) in association with serum calcium were identified and replicated. Rs1570669 near CYP24A1 (P = 9.1E-12), rs10491003 upstream of GATA3 (P = 4.8E-09) and rs7481584 in CARS (P = 1.2E-10) implicate regions involved in Mendelian calcemic disorders: Rs1550532 in DGKD (P = 8.2E-11), also associated with bone density, and rs7336933 near DGKH/KIAA0564 (P = 9.1E-10) are near genes that encode distinct isoforms of diacylglycerol kinase. Rs780094 is in GCKR. We characterized the expression of these genes in gut, kidney, and bone, and demonstrate modulation of gene expression in bone in response to dietary calcium in mice. Our results shed new light on the genetics of calcium homeostasis.
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Systematic identification of trans eQTLs as putative drivers of known disease associations.
Nat. Genet.
PUBLISHED: 08-14-2013
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Identifying the downstream effects of disease-associated SNPs is challenging. To help overcome this problem, we performed expression quantitative trait locus (eQTL) meta-analysis in non-transformed peripheral blood samples from 5,311 individuals with replication in 2,775 individuals. We identified and replicated trans eQTLs for 233 SNPs (reflecting 103 independent loci) that were previously associated with complex traits at genome-wide significance. Some of these SNPs affect multiple genes in trans that are known to be altered in individuals with disease: rs4917014, previously associated with systemic lupus erythematosus (SLE), altered gene expression of C1QB and five type I interferon response genes, both hallmarks of SLE. DeepSAGE RNA sequencing showed that rs4917014 strongly alters the 3 UTR levels of IKZF1 in cis, and chromatin immunoprecipitation and sequencing analysis of the trans-regulated genes implicated IKZF1 as the causal gene. Variants associated with cholesterol metabolism and type 1 diabetes showed similar phenomena, indicating that large-scale eQTL mapping provides insight into the downstream effects of many trait-associated variants.
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Rare variants in LRRK1 and Parkinsons disease.
Neurogenetics
PUBLISHED: 07-28-2013
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Approximately 20 % of individuals with Parkinsons disease (PD) report a positive family history. Yet, a large portion of causal and disease-modifying variants is still unknown. We used exome sequencing in two affected individuals from a family with late-onset PD to identify 15 potentially causal variants. Segregation analysis and frequency assessment in 862 PD cases and 1,014 ethnically matched controls highlighted variants in EEF1D and LRRK1 as the best candidates. Mutation screening of the coding regions of these genes in 862 cases and 1,014 controls revealed several novel non-synonymous variants in both genes in cases and controls. An in silico multi-model bioinformatics analysis was used to prioritize identified variants in LRRK1 for functional follow-up. However, protein expression, subcellular localization, and cell viability were not affected by the identified variants. Although it has yet to be proven conclusively that variants in LRRK1 are indeed causative of PD, our data strengthen a possible role for LRRK1 in addition to LRRK2 in the genetic underpinnings of PD but, at the same time, highlight the difficulties encountered in the study of rare variants identified by next-generation sequencing in diseases with autosomal dominant or complex patterns of inheritance.
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Macrocytic anemia and mitochondriopathy resulting from a defect in sideroflexin 4.
Am. J. Hum. Genet.
PUBLISHED: 07-21-2013
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We used exome sequencing to identify mutations in sideroflexin 4 (SFXN4) in two children with mitochondrial disease (the more severe case also presented with macrocytic anemia). SFXN4 is an uncharacterized mitochondrial protein that localizes to the mitochondrial inner membrane. sfxn4 knockdown in zebrafish recapitulated the mitochondrial respiratory defect observed in both individuals and the macrocytic anemia with megaloblastic features of the more severe case. In vitro and in vivo complementation studies with fibroblasts from the affected individuals and zebrafish demonstrated the requirement of SFXN4 for mitochondrial respiratory homeostasis and erythropoiesis. Our findings establish mutations in SFXN4 as a cause of mitochondriopathy and macrocytic anemia.
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A genome-wide association study identifies 6p21 as novel risk locus for dilated cardiomyopathy.
Eur. Heart J.
PUBLISHED: 07-12-2013
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Dilated cardiomyopathy (DCM) is one of the leading causes for cardiac transplantations and accounts for up to one-third of all heart failure cases. Since extrinsic and monogenic causes explain only a fraction of all cases, common genetic variants are suspected to contribute to the pathogenesis of DCM, its age of onset, and clinical progression. By a large-scale case-control genome-wide association study we aimed here to identify novel genetic risk loci for DCM.
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Rare sequence variants in ANO3 and GNAL in a primary torsion dystonia series and controls.
Mov. Disord.
PUBLISHED: 06-05-2013
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Rare autosomal-dominant mutations in ANO3 and GNAL have been recently shown to represent novel genetic factors underlying primary torsion dystonia (PTD) with predominantly craniocervical involvement.
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Genome-wide meta-analysis identifies new susceptibility loci for migraine.
Verneri Anttila, Bendik S Winsvold, Padhraig Gormley, Tobias Kurth, Francesco Bettella, George McMahon, Mikko Kallela, Rainer Malik, Boukje de Vries, Gisela Terwindt, Sarah E Medland, Unda Todt, Wendy L McArdle, Lydia Quaye, Markku Koiranen, M Arfan Ikram, Terho Lehtimäki, Anine H Stam, Lannie Ligthart, Juho Wedenoja, Ian Dunham, Benjamin M Neale, Priit Palta, Eija Hämäläinen, Markus Schürks, Lynda M Rose, Julie E Buring, Paul M Ridker, Stacy Steinberg, Hreinn Stefansson, Finnbogi Jakobsson, Debbie A Lawlor, David M Evans, Susan M Ring, Markus Färkkilä, Ville Artto, Mari A Kaunisto, Tobias Freilinger, Jean Schoenen, Rune R Frants, Nadine Pelzer, Claudia M Weller, Ronald Zielman, Andrew C Heath, Pamela A F Madden, Grant W Montgomery, Nicholas G Martin, Guntram Borck, Hartmut Göbel, Axel Heinze, Katja Heinze-Kuhn, Frances M K Williams, Anna-Liisa Hartikainen, Anneli Pouta, Joyce van den Ende, André G Uitterlinden, Albert Hofman, Najaf Amin, Jouke-Jan Hottenga, Jacqueline M Vink, Kauko Heikkilä, Michael Alexander, Bertram Müller-Myhsok, Stefan Schreiber, Thomas Meitinger, Heinz Erich Wichmann, Arpo Aromaa, Johan G Eriksson, Bryan J Traynor, Daniah Trabzuni, Elizabeth Rossin, Kasper Lage, Suzanne B R Jacobs, J Raphael Gibbs, Ewan Birney, Jaakko Kaprio, Brenda W Penninx, Dorret I Boomsma, Cornelia van Duijn, Olli Raitakari, Marjo-Riitta Järvelin, John-Anker Zwart, Lynn Cherkas, David P Strachan, Christian Kubisch, Michel D Ferrari, Arn M J M van den Maagdenberg, Martin Dichgans, Maija Wessman, George Davey Smith, Kari Stefansson, Mark J Daly, Dale R Nyholt, Daniel I Chasman, Aarno Palotie, .
Nat. Genet.
PUBLISHED: 05-30-2013
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Migraine is the most common brain disorder, affecting approximately 14% of the adult population, but its molecular mechanisms are poorly understood. We report the results of a meta-analysis across 29 genome-wide association studies, including a total of 23,285 individuals with migraine (cases) and 95,425 population-matched controls. We identified 12 loci associated with migraine susceptibility (P<5×10(-8)). Five loci are new: near AJAP1 at 1p36, near TSPAN2 at 1p13, within FHL5 at 6q16, within C7orf10 at 7p14 and near MMP16 at 8q21. Three of these loci were identified in disease subgroup analyses. Brain tissue expression quantitative trait locus analysis suggests potential functional candidate genes at four loci: APOA1BP, TBC1D7, FUT9, STAT6 and ATP5B.
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?-Propeller protein-associated neurodegeneration: a new X-linked dominant disorder with brain iron accumulation.
Brain
PUBLISHED: 05-17-2013
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Neurodegenerative disorders with high iron in the basal ganglia encompass an expanding collection of single gene disorders collectively known as neurodegeneration with brain iron accumulation. These disorders can largely be distinguished from one another by their associated clinical and neuroimaging features. The aim of this study was to define the phenotype that is associated with mutations in WDR45, a new causative gene for neurodegeneration with brain iron accumulation located on the X chromosome. The study subjects consisted of WDR45 mutation-positive individuals identified after screening a large international cohort of patients with idiopathic neurodegeneration with brain iron accumulation. Their records were reviewed, including longitudinal clinical, laboratory and imaging data. Twenty-three mutation-positive subjects were identified (20 females). The natural history of their disease was remarkably uniform: global developmental delay in childhood and further regression in early adulthood with progressive dystonia, parkinsonism and dementia. Common early comorbidities included seizures, spasticity and disordered sleep. The symptoms of parkinsonism improved with l-DOPA; however, nearly all patients experienced early motor fluctuations that quickly progressed to disabling dyskinesias, warranting discontinuation of l-DOPA. Brain magnetic resonance imaging showed iron in the substantia nigra and globus pallidus, with a halo of T1 hyperintense signal in the substantia nigra. All patients harboured de novo mutations in WDR45, encoding a beta-propeller protein postulated to play a role in autophagy. Beta-propeller protein-associated neurodegeneration, the only X-linked disorder of neurodegeneration with brain iron accumulation, is associated with de novo mutations in WDR45 and is recognizable by a unique combination of clinical, natural history and neuroimaging features.
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Mutations in FBXL4, encoding a mitochondrial protein, cause early-onset mitochondrial encephalomyopathy.
Am. J. Hum. Genet.
PUBLISHED: 05-14-2013
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Whole-exome sequencing and autozygosity mapping studies, independently performed in subjects with defective combined mitochondrial OXPHOS-enzyme deficiencies, identified a total of nine disease-segregating FBXL4 mutations in seven unrelated mitochondrial disease families, composed of six singletons and three siblings. All subjects manifested early-onset lactic acidemia, hypotonia, and developmental delay caused by severe encephalomyopathy consistently associated with progressive cerebral atrophy and variable involvement of the white matter, deep gray nuclei, and brainstem structures. A wide range of other multisystem features were variably seen, including dysmorphism, skeletal abnormalities, poor growth, gastrointestinal dysmotility, renal tubular acidosis, seizures, and episodic metabolic failure. Mitochondrial respiratory chain deficiency was present in muscle or fibroblasts of all tested individuals, together with markedly reduced oxygen consumption rate and hyperfragmentation of the mitochondrial network in cultured cells. In muscle and fibroblasts from several subjects, substantially decreased mtDNA content was observed. FBXL4 is a member of the F-box family of proteins, some of which are involved in phosphorylation-dependent ubiquitination and/or G protein receptor coupling. We also demonstrate that FBXL4 is targeted to mitochondria and localizes in the intermembrane space, where it participates in an approximately 400 kDa protein complex. These data strongly support a role for FBXL4 in controlling bioenergetic homeostasis and mtDNA maintenance. FBXL4 mutations are a recurrent cause of mitochondrial encephalomyopathy onset in early infancy.
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ELAC2 mutations cause a mitochondrial RNA processing defect associated with hypertrophic cardiomyopathy.
Am. J. Hum. Genet.
PUBLISHED: 04-11-2013
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The human mitochondrial genome encodes RNA components of its own translational machinery to produce the 13 mitochondrial-encoded subunits of the respiratory chain. Nuclear-encoded gene products are essential for all processes within the organelle, including RNA processing. Transcription of the mitochondrial genome generates large polycistronic transcripts punctuated by the 22 mitochondrial (mt) tRNAs that are conventionally cleaved by the RNase P-complex and the RNase Z activity of ELAC2 at 5 and 3 ends, respectively. We report the identification of mutations in ELAC2 in five individuals with infantile hypertrophic cardiomyopathy and complex I deficiency. We observed accumulated mtRNA precursors in affected individuals muscle and fibroblasts. Although mature mt-tRNA, mt-mRNA, and mt-rRNA levels were not decreased in fibroblasts, the processing defect was associated with impaired mitochondrial translation. Complementation experiments in mutant cell lines restored RNA processing and a yeast model provided additional evidence for the disease-causal role of defective ELAC2, thereby linking mtRNA processing to human disease.
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Nine loci for ocular axial length identified through genome-wide association studies, including shared loci with refractive error.
Ching-Yu Cheng, Maria Schache, M Kamran Ikram, Terri L Young, Jeremy A Guggenheim, Veronique Vitart, Stuart MacGregor, Virginie J M Verhoeven, Veluchamy A Barathi, Jiemin Liao, Pirro G Hysi, Joan E Bailey-Wilson, Beate St Pourcain, John P Kemp, George McMahon, Nicholas J Timpson, David M Evans, Grant W Montgomery, Aniket Mishra, Ya Xing Wang, Jie Jin Wang, Elena Rochtchina, Ozren Polašek, Alan F Wright, Najaf Amin, Elisabeth M van Leeuwen, James F Wilson, Craig E Pennell, Cornelia M van Duijn, Paulus T V M de Jong, Johannes R Vingerling, Xin Zhou, Peng Chen, Ruoying Li, Wan-Ting Tay, Yingfeng Zheng, Merwyn Chew, , Kathryn P Burdon, Jamie E Craig, Sudha K Iyengar, Robert P Igo, Jonathan H Lass, Emily Y Chew, Toomas Haller, Evelin Mihailov, Andres Metspalu, Juho Wedenoja, Claire L Simpson, Robert Wojciechowski, René Höhn, Alireza Mirshahi, Tanja Zeller, Norbert Pfeiffer, Karl J Lackner, Thomas Bettecken, Thomas Meitinger, Konrad Oexle, Mario Pirastu, Laura Portas, Abhishek Nag, Katie M Williams, Ekaterina Yonova-Doing, Ronald Klein, Barbara E Klein, S Mohsen Hosseini, Andrew D Paterson, Kari-Matti Mäkelä, Terho Lehtimäki, Mika Kähönen, Olli Raitakari, Nagahisa Yoshimura, Fumihiko Matsuda, Li Jia Chen, Chi Pui Pang, Shea Ping Yip, Maurice K H Yap, Akira Meguro, Nobuhisa Mizuki, Hidetoshi Inoko, Paul J Foster, Jing Hua Zhao, Eranga Vithana, E-Shyong Tai, Qiao Fan, Liang Xu, Harry Campbell, Brian Fleck, Igor Rudan, Tin Aung, Albert Hofman, André G Uitterlinden, Goran Bencic, Chiea-Chuen Khor, Hannah Forward, Olavi Pärssinen, Paul Mitchell, Fernando Rivadeneira, Alex W Hewitt, Cathy Williams, Ben A Oostra, Yik-Ying Teo, Christopher J Hammond, Dwight Stambolian, David A Mackey, Caroline C W Klaver, Tien-Yin Wong, Seang-Mei Saw, Paul N Baird.
Am. J. Hum. Genet.
PUBLISHED: 03-15-2013
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Refractive errors are common eye disorders of public health importance worldwide. Ocular axial length (AL) is the major determinant of refraction and thus of myopia and hyperopia. We conducted a meta-analysis of genome-wide association studies for AL, combining 12,531 Europeans and 8,216 Asians. We identified eight genome-wide significant loci for AL (RSPO1, C3orf26, LAMA2, GJD2, ZNRF3, CD55, MIP, and ALPPL2) and confirmed one previously reported AL locus (ZC3H11B). Of the nine loci, five (LAMA2, GJD2, CD55, ALPPL2, and ZC3H11B) were associated with refraction in 18 independent cohorts (n = 23,591). Differential gene expression was observed for these loci in minus-lens-induced myopia mouse experiments and human ocular tissues. Two of the AL genes, RSPO1 and ZNRF3, are involved in Wnt signaling, a pathway playing a major role in the regulation of eyeball size. This study provides evidence of shared genes between AL and refraction, but importantly also suggests that these traits may have unique pathways.
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Meta-analysis of genome-wide association studies in five cohorts reveals common variants in RBFOX1, a regulator of tissue-specific splicing, associated with refractive error.
Hum. Mol. Genet.
PUBLISHED: 03-07-2013
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Visual refractive errors (REs) are complex genetic traits with a largely unknown etiology. To date, genome-wide association studies (GWASs) of moderate size have identified several novel risk markers for RE, measured here as mean spherical equivalent (MSE). We performed a GWAS using a total of 7280 samples from five cohorts: the Age-Related Eye Disease Study (AREDS); the KORA study (Cooperative Health Research in the Region of Augsburg); the Framingham Eye Study (FES); the Ogliastra Genetic Park-Talana (OGP-Talana) Study and the Multiethnic Study of Atherosclerosis (MESA). Genotyping was performed on Illumina and Affymetrix platforms with additional markers imputed to the HapMap II reference panel. We identified a new genome-wide significant locus on chromosome 16 (rs10500355, P = 3.9 × 10(-9)) in a combined discovery and replication set (26 953 samples). This single nucleotide polymorphism (SNP) is located within the RBFOX1 gene which is a neuron-specific splicing factor regulating a wide range of alternative splicing events implicated in neuronal development and maturation, including transcription factors, other splicing factors and synaptic proteins.
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Assessment of the genomic variation in a cattle population by re-sequencing of key animals at low to medium coverage.
BMC Genomics
PUBLISHED: 03-05-2013
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Genome- and population-wide re-sequencing would allow for most efficient detection of causal trait variants. However, despite a strong decrease of costs for next-generation sequencing in the last few years, re-sequencing of large numbers of individuals is not yet affordable. We therefore resorted to re-sequencing of a limited number of bovine animals selected to explain a major proportion of the populations genomic variation, so called key animals, in order to provide a catalogue of functional variants and a substrate for population- and genome-wide imputation of variable sites.
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Seven new loci associated with age-related macular degeneration.
Lars G Fritsche, Wei Chen, Matthew Schu, Brian L Yaspan, Yi Yu, Gudmar Thorleifsson, Donald J Zack, Satoshi Arakawa, Valentina Cipriani, Stephan Ripke, Robert P Igo, Gabriëlle H S Buitendijk, Xueling Sim, Daniel E Weeks, Robyn H Guymer, Joanna E Merriam, Peter J Francis, Gregory Hannum, Anita Agarwal, Ana Maria Armbrecht, Isabelle Audo, Tin Aung, Gaetano R Barile, Mustapha Benchaboune, Alan C Bird, Paul N Bishop, Kari E Branham, Matthew Brooks, Alexander J Brucker, William H Cade, Melinda S Cain, Peter A Campochiaro, Chi-Chao Chan, Ching-Yu Cheng, Emily Y Chew, Kimberly A Chin, Itay Chowers, David G Clayton, Radu Cojocaru, Yvette P Conley, Belinda K Cornes, Mark J Daly, Baljean Dhillon, Albert O Edwards, Evangelos Evangelou, Jesen Fagerness, Henry A Ferreyra, James S Friedman, Asbjorg Geirsdottir, Ronnie J George, Christian Gieger, Neel Gupta, Stephanie A Hagstrom, Simon P Harding, Christos Haritoglou, John R Heckenlively, Frank G Holz, Guy Hughes, John P A Ioannidis, Tatsuro Ishibashi, Peronne Joseph, Gyungah Jun, Yoichiro Kamatani, Nicholas Katsanis, Claudia N Keilhauer, Jane C Khan, Ivana K Kim, Yutaka Kiyohara, Barbara E K Klein, Ronald Klein, Jaclyn L Kovach, Igor Kozak, Clara J Lee, Kristine E Lee, Peter Lichtner, Andrew J Lotery, Thomas Meitinger, Paul Mitchell, Saddek Mohand-Saïd, Anthony T Moore, Denise J Morgan, Margaux A Morrison, Chelsea E Myers, Adam C Naj, Yusuke Nakamura, Yukinori Okada, Anton Orlin, M Carolina Ortube, Mohammad I Othman, Chris Pappas, Kyu Hyung Park, Gayle J T Pauer, Neal S Peachey, Olivier Poch, Rinki Ratna Priya, Robyn Reynolds, Andrea J Richardson, Raymond Ripp, Guenther Rudolph, Euijung Ryu, José-Alain Sahel, Debra A Schaumberg, Hendrik P N Scholl, Stephen G Schwartz, William K Scott, Humma Shahid, Haraldur Sigurdsson, Giuliana Silvestri, Theru A Sivakumaran, R Theodore Smith, Lucia Sobrin, Eric H Souied, Dwight E Stambolian, Hreinn Stefansson, Gwen M Sturgill-Short, Atsushi Takahashi, Nirubol Tosakulwong, Barbara J Truitt, Evangelia E Tsironi, André G Uitterlinden, Cornelia M van Duijn, Lingam Vijaya, Johannes R Vingerling, Eranga N Vithana, Andrew R Webster, H-Erich Wichmann, Thomas W Winkler, Tien Y Wong, Alan F Wright, Diana Zelenika, Ming Zhang, Ling Zhao, Kang Zhang, Michael L Klein, Gregory S Hageman, G Mark Lathrop, Kari Stefansson, Rando Allikmets, Paul N Baird, Michael B Gorin, Jie Jin Wang, Caroline C W Klaver, Johanna M Seddon, Margaret A Pericak-Vance, Sudha K Iyengar, John R W Yates, Anand Swaroop, Bernhard H F Weber, Michiaki Kubo, Margaret M DeAngelis, Thierry Léveillard, Unnur Thorsteinsdottir, Jonathan L Haines, Lindsay A Farrer, Iris M Heid, Gonçalo R Abecasis, .
Nat. Genet.
PUBLISHED: 03-03-2013
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Age-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate the understanding of AMD biology and help design new therapies, we executed a collaborative genome-wide association study, including >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 loci associated at P < 5 × 10(-8). These loci show enrichment for genes involved in the regulation of complement activity, lipid metabolism, extracellular matrix remodeling and angiogenesis. Our results include seven loci with associations reaching P < 5 × 10(-8) for the first time, near the genes COL8A1-FILIP1L, IER3-DDR1, SLC16A8, TGFBR1, RAD51B, ADAMTS9 and B3GALTL. A genetic risk score combining SNP genotypes from all loci showed similar ability to distinguish cases and controls in all samples examined. Our findings provide new directions for biological, genetic and therapeutic studies of AMD.
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Transcriptome and genome sequencing uncovers functional variation in humans.
Nature
PUBLISHED: 02-07-2013
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Genome sequencing projects are discovering millions of genetic variants in humans, and interpretation of their functional effects is essential for understanding the genetic basis of variation in human traits. Here we report sequencing and deep analysis of messenger RNA and microRNA from lymphoblastoid cell lines of 462 individuals from the 1000 Genomes Project--the first uniformly processed high-throughput RNA-sequencing data from multiple human populations with high-quality genome sequences. We discover extremely widespread genetic variation affecting the regulation of most genes, with transcript structure and expression level variation being equally common but genetically largely independent. Our characterization of causal regulatory variation sheds light on the cellular mechanisms of regulatory and loss-of-function variation, and allows us to infer putative causal variants for dozens of disease-associated loci. Altogether, this study provides a deep understanding of the cellular mechanisms of transcriptome variation and of the landscape of functional variants in the human genome.
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Calmodulin mutations associated with recurrent cardiac arrest in infants.
Circulation
PUBLISHED: 02-06-2013
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Life-threatening disorders of heart rhythm may arise during infancy and can result in the sudden and tragic death of a child. We performed exome sequencing on 2 unrelated infants presenting with recurrent cardiac arrest to discover a genetic cause.
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Genome-wide meta-analyses of multiancestry cohorts identify multiple new susceptibility loci for refractive error and myopia.
Virginie J M Verhoeven, Pirro G Hysi, Robert Wojciechowski, Qiao Fan, Jeremy A Guggenheim, René Höhn, Stuart MacGregor, Alex W Hewitt, Abhishek Nag, Ching-Yu Cheng, Ekaterina Yonova-Doing, Xin Zhou, M Kamran Ikram, Gabriëlle H S Buitendijk, George McMahon, John P Kemp, Beate St Pourcain, Claire L Simpson, Kari-Matti Mäkelä, Terho Lehtimäki, Mika Kähönen, Andrew D Paterson, S Mohsen Hosseini, Hoi Suen Wong, Liang Xu, Jost B Jonas, Olavi Pärssinen, Juho Wedenoja, Shea Ping Yip, Daniel W H Ho, Chi Pui Pang, Li Jia Chen, Kathryn P Burdon, Jamie E Craig, Barbara E K Klein, Ronald Klein, Toomas Haller, Andres Metspalu, Chiea-Chuen Khor, E-Shyong Tai, Tin Aung, Eranga Vithana, Wan-Ting Tay, Veluchamy A Barathi, , Peng Chen, Ruoying Li, Jiemin Liao, Yingfeng Zheng, Rick T Ong, Angela Döring, David M Evans, Nicholas J Timpson, Annemieke J M H Verkerk, Thomas Meitinger, Olli Raitakari, Felicia Hawthorne, Tim D Spector, Lennart C Karssen, Mario Pirastu, Federico Murgia, Wei Ang, Aniket Mishra, Grant W Montgomery, Craig E Pennell, Phillippa M Cumberland, Ioana Cotlarciuc, Paul Mitchell, Jie Jin Wang, Maria Schache, Sarayut Janmahasatian, Sarayut Janmahasathian, Robert P Igo, Jonathan H Lass, Emily Chew, Sudha K Iyengar, Theo G M F Gorgels, Igor Rudan, Caroline Hayward, Alan F Wright, Ozren Polašek, Zoran Vatavuk, James F Wilson, Brian Fleck, Tanja Zeller, Alireza Mirshahi, Christian Müller, André G Uitterlinden, Fernando Rivadeneira, Johannes R Vingerling, Albert Hofman, Ben A Oostra, Najaf Amin, Arthur A B Bergen, Yik-Ying Teo, Jugnoo S Rahi, Veronique Vitart, Cathy Williams, Paul N Baird, Tien-Yin Wong, Konrad Oexle, Norbert Pfeiffer, David A Mackey, Terri L Young, Cornelia M van Duijn, Seang-Mei Saw, Joan E Bailey-Wilson, Dwight Stambolian, Caroline C Klaver, Christopher J Hammond.
Nat. Genet.
PUBLISHED: 01-16-2013
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Refractive error is the most common eye disorder worldwide and is a prominent cause of blindness. Myopia affects over 30% of Western populations and up to 80% of Asians. The CREAM consortium conducted genome-wide meta-analyses, including 37,382 individuals from 27 studies of European ancestry and 8,376 from 5 Asian cohorts. We identified 16 new loci for refractive error in individuals of European ancestry, of which 8 were shared with Asians. Combined analysis identified 8 additional associated loci. The new loci include candidate genes with functions in neurotransmission (GRIA4), ion transport (KCNQ5), retinoic acid metabolism (RDH5), extracellular matrix remodeling (LAMA2 and BMP2) and eye development (SIX6 and PRSS56). We also confirmed previously reported associations with GJD2 and RASGRF1. Risk score analysis using associated SNPs showed a tenfold increased risk of myopia for individuals carrying the highest genetic load. Our results, based on a large meta-analysis across independent multiancestry studies, considerably advance understanding of the mechanisms involved in refractive error and myopia.
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Loss-of-function mutations in MGME1 impair mtDNA replication and cause multisystemic mitochondrial disease.
Nat. Genet.
PUBLISHED: 01-13-2013
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Known disease mechanisms in mitochondrial DNA (mtDNA) maintenance disorders alter either the mitochondrial replication machinery (POLG, POLG2 and C10orf2) or the biosynthesis pathways of deoxyribonucleoside 5-triphosphates for mtDNA synthesis. However, in many of these disorders, the underlying genetic defect has yet to be discovered. Here, we identify homozygous nonsense and missense mutations in the orphan gene C20orf72 in three families with a mitochondrial syndrome characterized by external ophthalmoplegia, emaciation and respiratory failure. Muscle biopsies showed mtDNA depletion and multiple mtDNA deletions. C20orf72, hereafter MGME1 (mitochondrial genome maintenance exonuclease 1), encodes a mitochondrial RecB-type exonuclease belonging to the PD-(D/E)XK nuclease superfamily. We show that MGME1 cleaves single-stranded DNA and processes DNA flap substrates. Fibroblasts from affected individuals do not repopulate after chemically induced mtDNA depletion. They also accumulate intermediates of stalled replication and show increased levels of 7S DNA, as do MGME1-depleted cells. Thus, we show that MGME1-mediated mtDNA processing is essential for mitochondrial genome maintenance.
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Anal atresia, coloboma, microphthalmia, and nasal skin tag in a female patient with 3.5?Mb deletion of 3q26 encompassing SOX2.
Am. J. Med. Genet. A
PUBLISHED: 01-11-2013
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A full term female newborn presented with prominent forehead, bilateral microphthalmia, iris coloboma and cataract, wide intercanthal distance, large, low-set and protruding ears, skin tag at the left nasal nostril, imperforate anus with rectovestibular fistula, and postnatal growth delay with brachymicrocephaly. A marker chromosome was not detectable and the copy number of 22q11 was normal. However, array CGH revealed a 3.5?Mb microdeletion of chromosome region 3q26.32-3q26.33 (chr. 3: 178,598,162-182,114,483; hg19) which comprised the SOX2 gene. While SOX2 haploinsufficiency is known to cause microphthalmia and coloboma, it has not been described before in patients with anal atresia.
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Somatic mutations in ATP1A1 and ATP2B3 lead to aldosterone-producing adenomas and secondary hypertension.
Nat. Genet.
PUBLISHED: 01-09-2013
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Primary aldosteronism is the most prevalent form of secondary hypertension. To explore molecular mechanisms of autonomous aldosterone secretion, we performed exome sequencing of aldosterone-producing adenomas (APAs). We identified somatic hotspot mutations in the ATP1A1 (encoding an Na(+)/K(+) ATPase ? subunit) and ATP2B3 (encoding a Ca(2+) ATPase) genes in three and two of the nine APAs, respectively. These ATPases are expressed in adrenal cells and control sodium, potassium and calcium ion homeostasis. Functional in vitro studies of ATP1A1 mutants showed loss of pump activity and strongly reduced affinity for potassium. Electrophysiological ex vivo studies on primary adrenal adenoma cells provided further evidence for inappropriate depolarization of cells with ATPase alterations. In a collection of 308 APAs, we found 16 (5.2%) somatic mutations in ATP1A1 and 5 (1.6%) in ATP2B3. Mutation-positive cases showed male dominance, increased plasma aldosterone concentrations and lower potassium concentrations compared with mutation-negative cases. In summary, dominant somatic alterations in two members of the ATPase gene family result in autonomous aldosterone secretion.
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Niemann-Pick C Disease Gene Mutations and Age-Related Neurodegenerative Disorders.
PLoS ONE
PUBLISHED: 01-01-2013
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Niemann-Pick type C (NPC) disease is a rare autosomal-recessively inherited lysosomal storage disorder caused by mutations in NPC1 (95%) or NPC2. Given the highly variable phenotype, diagnosis is challenging and particularly late-onset forms with predominantly neuropsychiatric presentations are likely underdiagnosed. Pathophysiologically, genetic alterations compromising the endosomal/lysosomal system are linked with age-related neurodegenerative disorders. We sought to examine a possible association of rare sequence variants in NPC1 and NPC2 with Parkinsons disease (PD), frontotemporal lobar degeneration (FTLD) and progressive supranuclear palsy (PSP), and to genetically determine the proportion of potentially misdiagnosed NPC patients in these neurodegenerative conditions. By means of high-resolution melting, we screened the coding regions of NPC1 and NPC2 for rare genetic variation in a homogenous German sample of patients clinically diagnosed with PD (n?=?563), FTLD (n?=?133) and PSP (n?=?94), and 846 population-based controls. The frequencies of rare sequence variants in NPC1/2 did not differ significantly between patients and controls. Disease-associated NPC1/2 mutations were found in six PD patients (1.1%) and seven control subjects (0.8%), but not in FTLD or PSP. All rare variation was detected in the heterozygous state and no compound heterozygotes were observed. Our data do not support the hypothesis that rare NPC1/2 variants confer susceptibility for PD, FTLD, or PSP in the German population. Misdiagnosed NPC patients were not present in our samples. However, further assessment of NPC disease genes in age-related neurodegeneration is warranted.
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Mutation screening of 75 candidate genes in 152 complex I deficiency cases identifies pathogenic variants in 16 genes including NDUFB9.
J. Med. Genet.
PUBLISHED: 12-26-2011
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Mitochondrial complex I deficiency is the most common cause of mitochondrial disease in childhood. Identification of the molecular basis is difficult given the clinical and genetic heterogeneity. Most patients lack a molecular definition in routine diagnostics.
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A one base pair deletion in the canine ATP13A2 gene causes exon skipping and late-onset neuronal ceroid lipofuscinosis in the Tibetan terrier.
PLoS Genet.
PUBLISHED: 08-06-2011
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Neuronal ceroid lipofuscinosis (NCL) is a progressive neurodegenerative disease characterized by brain and retinal atrophy and the intracellular accumulation of autofluorescent lysosomal storage bodies resembling lipofuscin in neurons and other cells. Tibetan terriers show a late-onset lethal form of NCL manifesting first visible signs at 5-7 years of age. Genome-wide association analyses for 12 Tibetan-terrier-NCL-cases and 7 Tibetan-terrier controls using the 127K canine Affymetrix SNP chip and mixed model analysis mapped NCL to dog chromosome (CFA) 2 at 83.71-84.72 Mb. Multipoint linkage and association analyses in 376 Tibetan terriers confirmed this genomic region on CFA2. A mutation analysis for 14 positional candidate genes in two NCL-cases and one control revealed a strongly associated single nucleotide polymorphism (SNP) in the MAPK PM20/PM21 gene and a perfectly with NCL associated single base pair deletion (c.1620delG) within exon 16 of the ATP13A2 gene. The c.1620delG mutation in ATP13A2 causes skipping of exon 16 presumably due to a broken exonic splicing enhancer motif. As a result of this mutation, ATP13A2 lacks 69 amino acids. All known 24 NCL cases were homozygous for this deletion and all obligate 35 NCL-carriers were heterozygous. In a sample of 144 dogs from eleven other breeds, the c.1620delG mutation could not be found. Knowledge of the causative mutation for late-onset NCL in Tibetan terrier allows genetic testing of these dogs to avoid matings of carrier animals. ATP13A2 mutations have been described in familial Parkinson syndrome (PARK9). Tibetan terriers with these mutations provide a valuable model for a PARK9-linked disease and possibly for manganese toxicity in synucleinopathies.
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Absence of an orphan mitochondrial protein, c19orf12, causes a distinct clinical subtype of neurodegeneration with brain iron accumulation.
Am. J. Hum. Genet.
PUBLISHED: 08-01-2011
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The disease classification neurodegeneration with brain iron accumulation (NBIA) comprises a clinically and genetically heterogeneous group of progressive neurodegenerative disorders characterized by brain iron deposits in the basal ganglia. For about half of the cases, the molecular basis is currently unknown. We used homozygosity mapping followed by candidate gene sequencing to identify a homozygous 11 bp deletion in the orphan gene C19orf12. Mutation screening of 23 ideopathic NBIA index cases revealed two mutated alleles in 18 of them, and one loss-of-function mutation is the most prevalent. We also identified compound heterozygous missense mutations in a case initially diagnosed with Parkinson disease at age 49. Psychiatric signs, optic atrophy, and motor axonal neuropathy were common findings. Compared to the most prevalent NBIA subtype, pantothenate kinase associated neurodegeneration (PKAN), individuals with two C19orf12 mutations were older at age of onset and the disease progressed more slowly. A polyclonal antibody against the predicted membrane spanning protein showed a mitochondrial localization. A histopathological examination in a single autopsy case detected Lewy bodies, tangles, spheroids, and tau pathology. The mitochondrial localization together with the immunohistopathological findings suggests a pathomechanistic overlap with common forms of neurodegenerative disorders.
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Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk.
, Georg B Ehret, Patricia B Munroe, Kenneth M Rice, Murielle Bochud, Andrew D Johnson, Daniel I Chasman, Albert V Smith, Martin D Tobin, Germaine C Verwoert, Shih-Jen Hwang, Vasyl Pihur, Peter Vollenweider, Paul F O'Reilly, Najaf Amin, Jennifer L Bragg-Gresham, Alexander Teumer, Nicole L Glazer, Lenore Launer, Jing Hua Zhao, Yurii Aulchenko, Simon Heath, Siim Sõber, Afshin Parsa, Jian'an Luan, Pankaj Arora, Abbas Dehghan, Feng Zhang, Gavin Lucas, Andrew A Hicks, Anne U Jackson, John F Peden, Toshiko Tanaka, Sarah H Wild, Igor Rudan, Wilmar Igl, Yuri Milaneschi, Alex N Parker, Cristiano Fava, John C Chambers, Ervin R Fox, Meena Kumari, Min Jin Go, Pim van der Harst, Wen Hong Linda Kao, Marketa Sjögren, D G Vinay, Myriam Alexander, Yasuharu Tabara, Sue Shaw-Hawkins, Peter H Whincup, Yongmei Liu, Gang Shi, Johanna Kuusisto, Bamidele Tayo, Mark Seielstad, Xueling Sim, Khanh-Dung Hoang Nguyen, Terho Lehtimäki, Giuseppe Matullo, Ying Wu, Tom R Gaunt, N Charlotte Onland-Moret, Matthew N Cooper, Carl G P Platou, Elin Org, Rebecca Hardy, Santosh Dahgam, Jutta Palmen, Veronique Vitart, Peter S Braund, Tatiana Kuznetsova, Cuno S P M Uiterwaal, Adebowale Adeyemo, Walter Palmas, Harry Campbell, Barbara Ludwig, Maciej Tomaszewski, Ioanna Tzoulaki, Nicholette D Palmer, Thor Aspelund, Melissa Garcia, Yen-Pei C Chang, Jeffrey R O'Connell, Nanette I Steinle, Diederick E Grobbee, Dan E Arking, Sharon L Kardia, Alanna C Morrison, Dena Hernandez, Samer Najjar, Wendy L McArdle, David Hadley, Morris J Brown, John M Connell, Aroon D Hingorani, Ian N M Day, Debbie A Lawlor, John P Beilby, Robert W Lawrence, Robert Clarke, Jemma C Hopewell, Halit Ongen, Albert W Dreisbach, Yali Li, J Hunter Young, Joshua C Bis, Mika Kähönen, Jorma Viikari, Linda S Adair, Nanette R Lee, Ming-Huei Chen, Matthias Olden, Cristian Pattaro, Judith A Hoffman Bolton, Anna Köttgen, Sven Bergmann, Vincent Mooser, Nish Chaturvedi, Timothy M Frayling, Muhammad Islam, Tazeen H Jafar, Jeanette Erdmann, Smita R Kulkarni, Stefan R Bornstein, Jürgen Gräßler, Leif Groop, Benjamin F Voight, Johannes Kettunen, Philip Howard, Andrew Taylor, Simonetta Guarrera, Fulvio Ricceri, Valur Emilsson, Andrew Plump, Inês Barroso, Kay-Tee Khaw, Alan B Weder, Steven C Hunt, Yan V Sun, Richard N Bergman, Francis S Collins, Lori L Bonnycastle, Laura J Scott, Heather M Stringham, Leena Peltonen, Markus Perola, Erkki Vartiainen, Stefan-Martin Brand, Jan A Staessen, Thomas J Wang, Paul R Burton, María Soler Artigas, Yanbin Dong, Harold Snieder, Xiaoling Wang, Haidong Zhu, Kurt K Lohman, Megan E Rudock, Susan R Heckbert, Nicholas L Smith, Kerri L Wiggins, Ayo Doumatey, Daniel Shriner, Gudrun Veldre, Margus Viigimaa, Sanjay Kinra, Dorairaj Prabhakaran, Vikal Tripathy, Carl D Langefeld, Annika Rosengren, Dag S Thelle, Anna Maria Corsi, Andrew Singleton, Terrence Forrester, Gina Hilton, Colin A McKenzie, Tunde Salako, Naoharu Iwai, Yoshikuni Kita, Toshio Ogihara, Takayoshi Ohkubo, Tomonori Okamura, Hirotsugu Ueshima, Satoshi Umemura, Susana Eyheramendy, Thomas Meitinger, H-Erich Wichmann, Yoon Shin Cho, Hyung-Lae Kim, Jong-Young Lee, James Scott, Joban S Sehmi, Weihua Zhang, Bo Hedblad, Peter Nilsson, George Davey Smith, Andrew Wong, Narisu Narisu, Alena Stančáková, Leslie J Raffel, Jie Yao, Sekar Kathiresan, Christopher J O'Donnell, Stephen M Schwartz, M Arfan Ikram, W T Longstreth, Thomas H Mosley, Sudha Seshadri, Nick R G Shrine, Louise V Wain, Mario A Morken, Amy J Swift, Jaana Laitinen, Inga Prokopenko, Paavo Zitting, Jackie A Cooper, Steve E Humphries, John Danesh, Asif Rasheed, Anuj Goel, Anders Hamsten, Hugh Watkins, Stephan J L Bakker, Wiek H van Gilst, Charles S Janipalli, K Radha Mani, Chittaranjan S Yajnik, Albert Hofman, Francesco U S Mattace-Raso, Ben A Oostra, Ayse Demirkan, Aaron Isaacs, Fernando Rivadeneira, Edward G Lakatta, Marco Orrù, Angelo Scuteri, Mika Ala-Korpela, Antti J Kangas, Leo-Pekka Lyytikäinen, Pasi Soininen, Taru Tukiainen, Peter Würtz, Rick Twee-Hee Ong, Marcus Dörr, Heyo K Kroemer, Uwe Völker, Henry Völzke, Pilar Galán, Serge Hercberg, Mark Lathrop, Diana Zelenika, Panos Deloukas, Massimo Mangino, Tim D Spector, Guangju Zhai, James F Meschia, Michael A Nalls, Pankaj Sharma, Janos Terzic, M V Kranthi Kumar, Matthew Denniff, Ewa Zukowska-Szczechowska, Lynne E Wagenknecht, F Gerald R Fowkes, Fadi J Charchar, Peter E H Schwarz, Caroline Hayward, Xiuqing Guo, Charles Rotimi, Michiel L Bots, Eva Brand, Nilesh J Samani, Ozren Polašek, Philippa J Talmud, Fredrik Nyberg, Diana Kuh, Maris Laan, Kristian Hveem, Lyle J Palmer, Yvonne T van der Schouw, Juan P Casas, Karen L Mohlke, Paolo Vineis, Olli Raitakari, Santhi K Ganesh, Tien Y Wong, E Shyong Tai, Richard S Cooper, Markku Laakso, Dabeeru C Rao, Tamara B Harris, Richard W Morris, Anna F Dominiczak, Mika Kivimäki, Michael G Marmot, Tetsuro Miki, Danish Saleheen, Giriraj R Chandak, Josef Coresh, Gerjan Navis, Veikko Salomaa, Bok-Ghee Han, Xiaofeng Zhu, Jaspal S Kooner, Olle Melander, Paul M Ridker, Stefania Bandinelli, Ulf B Gyllensten, Alan F Wright, James F Wilson, Luigi Ferrucci, Martin Farrall, Jaakko Tuomilehto, Peter P Pramstaller, Roberto Elosua, Nicole Soranzo, Eric J G Sijbrands, David Altshuler, Ruth J F Loos, Alan R Shuldiner, Christian Gieger, Pierre Meneton, André G Uitterlinden, Nicholas J Wareham, Vilmundur Gudnason, Jerome I Rotter, Rainer Rettig, Manuela Uda, David P Strachan, Jacqueline C M Witteman, Anna-Liisa Hartikainen, Jacques S Beckmann, Eric Boerwinkle, Ramachandran S Vasan, Michael Boehnke, Martin G Larson, Marjo-Riitta Järvelin, Bruce M Psaty, Gonçalo R Abecasis, Aravinda Chakravarti, Paul Elliott, Cornelia M van Duijn, Christopher Newton-Cheh, Daniel Levy, Mark J Caulfield, Toby Johnson.
Nature
PUBLISHED: 07-28-2011
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Blood pressure is a heritable trait influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (?140?mm?Hg systolic blood pressure or? ?90?mm?Hg diastolic blood pressure). Even small increments in blood pressure are associated with an increased risk of cardiovascular events. This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention.
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Variants in STAT5B associate with serum TC and LDL-C levels.
J. Clin. Endocrinol. Metab.
PUBLISHED: 07-13-2011
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Known genetic variants influencing serum lipid levels do not adequately account for the observed population variability of these phenotypes. The GH/signal transducers and activators of transcription (STAT) signaling pathway is an evolutionary conserved system that exerts strong effects on metabolism, including that of lipids.
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Human metabolic individuality in biomedical and pharmaceutical research.
Nature
PUBLISHED: 06-30-2011
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Genome-wide association studies (GWAS) have identified many risk loci for complex diseases, but effect sizes are typically small and information on the underlying biological processes is often lacking. Associations with metabolic traits as functional intermediates can overcome these problems and potentially inform individualized therapy. Here we report a comprehensive analysis of genotype-dependent metabolic phenotypes using a GWAS with non-targeted metabolomics. We identified 37 genetic loci associated with blood metabolite concentrations, of which 25 show effect sizes that are unusually high for GWAS and account for 10-60% differences in metabolite levels per allele copy. Our associations provide new functional insights for many disease-related associations that have been reported in previous studies, including those for cardiovascular and kidney disorders, type 2 diabetes, cancer, gout, venous thromboembolism and Crohns disease. The study advances our knowledge of the genetic basis of metabolic individuality in humans and generates many new hypotheses for biomedical and pharmaceutical research.
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Discovery of sexual dimorphisms in metabolic and genetic biomarkers.
PLoS Genet.
PUBLISHED: 06-17-2011
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Metabolomic profiling and the integration of whole-genome genetic association data has proven to be a powerful tool to comprehensively explore gene regulatory networks and to investigate the effects of genetic variation at the molecular level. Serum metabolite concentrations allow a direct readout of biological processes, and association of specific metabolomic signatures with complex diseases such as Alzheimers disease and cardiovascular and metabolic disorders has been shown. There are well-known correlations between sex and the incidence, prevalence, age of onset, symptoms, and severity of a disease, as well as the reaction to drugs. However, most of the studies published so far did not consider the role of sexual dimorphism and did not analyse their data stratified by gender. This study investigated sex-specific differences of serum metabolite concentrations and their underlying genetic determination. For discovery and replication we used more than 3,300 independent individuals from KORA F3 and F4 with metabolite measurements of 131 metabolites, including amino acids, phosphatidylcholines, sphingomyelins, acylcarnitines, and C6-sugars. A linear regression approach revealed significant concentration differences between males and females for 102 out of 131 metabolites (p-values<3.8×10(-4); Bonferroni-corrected threshold). Sex-specific genome-wide association studies (GWAS) showed genome-wide significant differences in beta-estimates for SNPs in the CPS1 locus (carbamoyl-phosphate synthase 1, significance level: p<3.8×10(-10); Bonferroni-corrected threshold) for glycine. We showed that the metabolite profiles of males and females are significantly different and, furthermore, that specific genetic variants in metabolism-related genes depict sexual dimorphism. Our study provides new important insights into sex-specific differences of cell regulatory processes and underscores that studies should consider sex-specific effects in design and interpretation.
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A genome-wide association study confirms APOE as the major gene influencing survival in long-lived individuals.
Mech. Ageing Dev.
PUBLISHED: 06-14-2011
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We conducted a case-control genome-wide association study (GWAS) of human longevity, comparing 664,472 autosomal SNPs in 763 long-lived individuals (LLI; mean age: 99.7 years) and 1085 controls (mean age: 60.2 years) from Germany. Only one association, namely that of SNP rs4420638 near the APOC1 gene, achieved genome-wide significance (allele-based P=1.8×10(-10)). However, logistic regression analysis revealed that this association, which was replicated in an independent German sample, is fully explicable by linkage disequilibrium with the APOE allele ?4, the only variant hitherto established as a major genetic determinant of survival into old age. Our GWAS failed to identify any additional autosomal susceptibility genes. One explanation for this lack of success in our study would be that GWAS provide only limited statistical power for a polygenic phenotype with loci of small effect such as human longevity. A recent GWAS in Dutch LLI independently confirmed the APOE-longevity association, thus strengthening the conclusion that this locus is a very, if not the most, important genetic factor influencing longevity.
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Genome-wide association study identifies novel restless legs syndrome susceptibility loci on 2p14 and 16q12.1.
PLoS Genet.
PUBLISHED: 05-24-2011
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Restless legs syndrome (RLS) is a sensorimotor disorder with an age-dependent prevalence of up to 10% in the general population above 65 years of age. Affected individuals suffer from uncomfortable sensations and an urge to move in the lower limbs that occurs mainly in resting situations during the evening or at night. Moving the legs or walking leads to an improvement of symptoms. Concomitantly, patients report sleep disturbances with consequences such as reduced daytime functioning. We conducted a genome-wide association study (GWA) for RLS in 922 cases and 1,526 controls (using 301,406 SNPs) followed by a replication of 76 candidate SNPs in 3,935 cases and 5,754 controls, all of European ancestry. Herein, we identified six RLS susceptibility loci of genome-wide significance, two of them novel: an intergenic region on chromosome 2p14 (rs6747972, P?=?9.03 × 10(-11), OR?=?1.23) and a locus on 16q12.1 (rs3104767, P?=?9.4 × 10(-19), OR?=?1.35) in a linkage disequilibrium block of 140 kb containing the 5-end of TOX3 and the adjacent non-coding RNA BC034767.
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MEIS1 and BTBD9: genetic association with restless leg syndrome in end stage renal disease.
J. Med. Genet.
PUBLISHED: 05-14-2011
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Restless legs syndrome (RLS) is a sleep related movement disorder that occurs both in an idiopathic form and in symptomatic varieties. RLS is a frequent and distressing comorbidity in end stage renal disease (ESRD). For idiopathic RLS (iRLS), genetic risk factors have been identified, but their role in RLS in ESRD has not been investigated yet. Therefore, a case-control association study of these variants in ESRD patients was performed.
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A mutation in VPS35, encoding a subunit of the retromer complex, causes late-onset Parkinson disease.
Am. J. Hum. Genet.
PUBLISHED: 05-08-2011
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To identify rare causal variants in late-onset Parkinson disease (PD), we investigated an Austrian family with 16 affected individuals by exome sequencing. We found a missense mutation, c.1858G>A (p.Asp620Asn), in the VPS35 gene in all seven affected family members who are alive. By screening additional PD cases, we saw the same variant cosegregating with the disease in an autosomal-dominant mode with high but incomplete penetrance in two further families with five and ten affected members, respectively. The mean age of onset in the affected individuals was 53 years. Genotyping showed that the shared haplotype extends across 65 kilobases around VPS35. Screening the entire VPS35 coding sequence in an additional 860 cases and 1014 controls revealed six further nonsynonymous missense variants. Three were only present in cases, two were only present in controls, and one was present in cases and controls. The familial mutation p.Asp620Asn and a further variant, c.1570C>T (p.Arg524Trp), detected in a sporadic PD case were predicted to be damaging by sequence-based and molecular-dynamics analyses. VPS35 is a component of the retromer complex and mediates retrograde transport between endosomes and the trans-Golgi network, and it has recently been found to be involved in Alzheimer disease.
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Effect of genome-wide simultaneous hypotheses tests on the discovery rate.
Int J Mol Epidemiol Genet
PUBLISHED: 04-22-2011
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An increasing number of genome-wide association studies are being performed in hundreds of thousands of single nucleotide polymorphisms (SNPs). Many of such studies carry on a second stage in which a selected number of SNPs are genotyped in new individuals in order to validate genome-wide findings. Unfortunately, a large proportion of such studies have been unable to validate the genome-wide findings. In this study we aim to better understand how to distinguish the truly associated features from the false positives in genome-wide scans. In order to achieve this goal we use empirical data to look at three aspects that may play a key role in determining which features are called to be associated with the phenotype. First, we examine the usual assumption of a uniform distribution on null p-values and assess whether or not it affects which features are called significant and the number of significant features. Second, we compare the global behavior of the p-value distribution genome-wide with the local behavior at regions such as chromosomes. Third, we look at the effect of minor allele frequency in the p-value distribution. We show empirically that the uniform distribution is not a generally valid assumption and we find that as a consequence strikingly different conclusions can be drawn regarding what we call significant associations and the number of significant findings. We propose that in order to better assign significance to potential associations one needs to estimate the true distribution of null and non-null p-values.
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Genetic determinants of serum testosterone concentrations in men.
PLoS Genet.
PUBLISHED: 04-04-2011
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Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterones high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n?=?871) and two de novo replication cohorts (n?=?4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p?=?1.2×10(-41) and rs6258, p?=?2.3×10(-22)). Subjects with ? 3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p?=?5.6×10(-16)). The rs6258 polymorphism in exon 4 of SHBG affected SHBGs affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.
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Sampling GWAS subjects from risk populations.
Genet. Epidemiol.
PUBLISHED: 02-16-2011
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Power, i.e. sample size, is a crucial issue in genome-wide association studies (GWAS) on disorders generated by a multitude of weak genetic effects. Here, we examine the influence of sampling cases and/or controls from populations that are subjected to an external risk factor (such as smoking or nutritional factors). We use an additive threshold model and derive the necessary sample size as function of the external risk factors strength and of the sampling scheme. If both cases and controls are sampled from the risk population, a loss of power must be expected. The loss of power (i.e. the increase of the necessary sample size) is even larger if only the cases are sampled from the risk population, whereas the inverse scheme (nonrisk cases and risk controls) provides a gain of power since nonrisk cases are enriched for disease-favouring alleles while risk controls are enriched for protective alleles. For small effect sizes, we derive simple approximations in analytically closed form. A strategy of GWAS sample collection from risk populations minimizing the necessary sample sizes may thus be deduced that generally applies as long as strong gene-environment interactions can be excluded.
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Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure.
Louise V Wain, Germaine C Verwoert, Paul F O'Reilly, Gang Shi, Toby Johnson, Andrew D Johnson, Murielle Bochud, Kenneth M Rice, Peter Henneman, Albert V Smith, Georg B Ehret, Najaf Amin, Martin G Larson, Vincent Mooser, David Hadley, Marcus Dörr, Joshua C Bis, Thor Aspelund, Tonu Esko, A Cecile J W Janssens, Jing Hua Zhao, Simon Heath, Maris Laan, Jingyuan Fu, Giorgio Pistis, Jian'an Luan, Pankaj Arora, Gavin Lucas, Nicola Pirastu, Irene Pichler, Anne U Jackson, Rebecca J Webster, Feng Zhang, John F Peden, Helena Schmidt, Toshiko Tanaka, Harry Campbell, Wilmar Igl, Yuri Milaneschi, Jouke-Jan Hottenga, Veronique Vitart, Daniel I Chasman, Stella Trompet, Jennifer L Bragg-Gresham, Behrooz Z Alizadeh, John C Chambers, Xiuqing Guo, Terho Lehtimäki, Brigitte Kühnel, Lorna M Lopez, Ozren Polašek, Mladen Boban, Christopher P Nelson, Alanna C Morrison, Vasyl Pihur, Santhi K Ganesh, Albert Hofman, Suman Kundu, Francesco U S Mattace-Raso, Fernando Rivadeneira, Eric J G Sijbrands, André G Uitterlinden, Shih-Jen Hwang, Ramachandran S Vasan, Thomas J Wang, Sven Bergmann, Peter Vollenweider, Gérard Waeber, Jaana Laitinen, Anneli Pouta, Paavo Zitting, Wendy L McArdle, Heyo K Kroemer, Uwe Völker, Henry Völzke, Nicole L Glazer, Kent D Taylor, Tamara B Harris, Helene Alavere, Toomas Haller, Aime Keis, Mari-Liis Tammesoo, Yurii Aulchenko, Inês Barroso, Kay-Tee Khaw, Pilar Galán, Serge Hercberg, Mark Lathrop, Susana Eyheramendy, Elin Org, Siim Sõber, Xiaowen Lu, Ilja M Nolte, Brenda W Penninx, Tanguy Corre, Corrado Masciullo, Cinzia Sala, Leif Groop, Benjamin F Voight, Olle Melander, Christopher J O'Donnell, Veikko Salomaa, Adamo Pio D'adamo, Antonella Fabretto, Flavio Faletra, Sheila Ulivi, Fabiola M Del Greco, Maurizio Facheris, Francis S Collins, Richard N Bergman, John P Beilby, Joseph Hung, A William Musk, Massimo Mangino, So-Youn Shin, Nicole Soranzo, Hugh Watkins, Anuj Goel, Anders Hamsten, Pierre Gider, Marisa Loitfelder, Marion Zeginigg, Dena Hernandez, Samer S Najjar, Pau Navarro, Sarah H Wild, Anna Maria Corsi, Andrew Singleton, Eco J C de Geus, Gonneke Willemsen, Alex N Parker, Lynda M Rose, Brendan Buckley, David Stott, Marco Orrù, Manuela Uda, , Melanie M van der Klauw, Weihua Zhang, Xinzhong Li, James Scott, Yii-Der Ida Chen, Gregory L Burke, Mika Kähönen, Jorma Viikari, Angela Döring, Thomas Meitinger, Gail Davies, John M Starr, Valur Emilsson, Andrew Plump, Jan H Lindeman, Peter A C 't Hoen, Inke R König, Janine F Felix, Robert Clarke, Jemma C Hopewell, Halit Ongen, Monique Breteler, Stéphanie Debette, Anita L Destefano, Myriam Fornage, Gary F Mitchell, Nicholas L Smith, Hilma Holm, Kari Stefansson, Gudmar Thorleifsson, Unnur Thorsteinsdottir, Nilesh J Samani, Michael Preuss, Igor Rudan, Caroline Hayward, Ian J Deary, H-Erich Wichmann, Olli T Raitakari, Walter Palmas, Jaspal S Kooner, Ronald P Stolk, J Wouter Jukema, Alan F Wright, Dorret I Boomsma, Stefania Bandinelli, Ulf B Gyllensten, James F Wilson, Luigi Ferrucci, Reinhold Schmidt, Martin Farrall, Tim D Spector, Lyle J Palmer, Jaakko Tuomilehto, Arne Pfeufer, Paolo Gasparini, David Siscovick, David Altshuler, Ruth J F Loos, Daniela Toniolo, Harold Snieder, Christian Gieger, Pierre Meneton, Nicholas J Wareham, Ben A Oostra, Andres Metspalu, Lenore Launer, Rainer Rettig, David P Strachan, Jacques S Beckmann, Jacqueline C M Witteman, Jeanette Erdmann, Ko Willems van Dijk, Eric Boerwinkle, Michael Boehnke, Paul M Ridker, Marjo-Riitta Järvelin, Aravinda Chakravarti, Gonçalo R Abecasis, Vilmundur Gudnason, Christopher Newton-Cheh, Daniel Levy, Patricia B Munroe, Bruce M Psaty, Mark J Caulfield, Dabeeru C Rao, Martin D Tobin, Paul Elliott, Cornelia M van Duijn.
Nat. Genet.
PUBLISHED: 02-10-2011
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Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we identified at genome-wide significance (P = 2.7 × 10(-8) to P = 2.3 × 10(-13)) four new PP loci (at 4q12 near CHIC2, 7q22.3 near PIK3CG, 8q24.12 in NOV and 11q24.3 near ADAMTS8), two new MAP loci (3p21.31 in MAP4 and 10q25.3 near ADRB1) and one locus associated with both of these traits (2q24.3 near FIGN) that has also recently been associated with SBP in east Asians. For three of the new PP loci, the estimated effect for SBP was opposite of that for DBP, in contrast to the majority of common SBP- and DBP-associated variants, which show concordant effects on both traits. These findings suggest new genetic pathways underlying blood pressure variation, some of which may differentially influence SBP and DBP.
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Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease.
Heribert Schunkert, Inke R König, Sekar Kathiresan, Muredach P Reilly, Themistocles L Assimes, Hilma Holm, Michael Preuss, Alexandre F R Stewart, Maja Barbalic, Christian Gieger, Devin Absher, Zouhair Aherrahrou, Hooman Allayee, David Altshuler, Sonia S Anand, Karl Andersen, Jeffrey L Anderson, Diego Ardissino, Stephen G Ball, Anthony J Balmforth, Timothy A Barnes, Diane M Becker, Lewis C Becker, Klaus Berger, Joshua C Bis, S Matthijs Boekholdt, Eric Boerwinkle, Peter S Braund, Morris J Brown, Mary Susan Burnett, Ian Buysschaert, , John F Carlquist, Li Chen, Sven Cichon, Veryan Codd, Robert W Davies, George Dedoussis, Abbas Dehghan, Serkalem Demissie, Joseph M Devaney, Patrick Diemert, Ron Do, Angela Doering, Sandra Eifert, Nour Eddine El Mokhtari, Stephen G Ellis, Roberto Elosua, James C Engert, Stephen E Epstein, Ulf de Faire, Marcus Fischer, Aaron R Folsom, Jennifer Freyer, Bruna Gigante, Domenico Girelli, Solveig Gretarsdottir, Vilmundur Gudnason, Jeffrey R Gulcher, Eran Halperin, Naomi Hammond, Stanley L Hazen, Albert Hofman, Benjamin D Horne, Thomas Illig, Carlos Iribarren, Gregory T Jones, J Wouter Jukema, Michael A Kaiser, Lee M Kaplan, John J P Kastelein, Kay-Tee Khaw, Joshua W Knowles, Genovefa Kolovou, Augustine Kong, Reijo Laaksonen, Diether Lambrechts, Karin Leander, Guillaume Lettre, Mingyao Li, Wolfgang Lieb, Christina Loley, Andrew J Lotery, Pier M Mannucci, Seraya Maouche, Nicola Martinelli, Pascal P McKeown, Christa Meisinger, Thomas Meitinger, Olle Melander, Pier Angelica Merlini, Vincent Mooser, Thomas Morgan, Thomas W Mühleisen, Joseph B Muhlestein, Thomas Münzel, Kiran Musunuru, Janja Nahrstaedt, Christopher P Nelson, Markus M Nöthen, Oliviero Olivieri, Riyaz S Patel, Chris C Patterson, Annette Peters, Flora Peyvandi, Liming Qu, Arshed A Quyyumi, Daniel J Rader, Loukianos S Rallidis, Catherine Rice, Frits R Rosendaal, Diana Rubin, Veikko Salomaa, M Lourdes Sampietro, Manj S Sandhu, Eric Schadt, Arne Schäfer, Arne Schillert, Stefan Schreiber, Jürgen Schrezenmeir, Stephen M Schwartz, David S Siscovick, Mohan Sivananthan, Suthesh Sivapalaratnam, Albert Smith, Tamara B Smith, Jaapjan D Snoep, Nicole Soranzo, John A Spertus, Klaus Stark, Kathy Stirrups, Monika Stoll, W H Wilson Tang, Stephanie Tennstedt, Gudmundur Thorgeirsson, Gudmar Thorleifsson, Maciej Tomaszewski, André G Uitterlinden, Andre M van Rij, Benjamin F Voight, Nick J Wareham, George A Wells, H-Erich Wichmann, Philipp S Wild, Christina Willenborg, Jaqueline C M Witteman, Benjamin J Wright, Shu Ye, Tanja Zeller, Andreas Ziegler, Francois Cambien, Alison H Goodall, L Adrienne Cupples, Thomas Quertermous, Winfried März, Christian Hengstenberg, Stefan Blankenberg, Willem H Ouwehand, Alistair S Hall, Panos Deloukas, John R Thompson, Kari Stefansson, Robert Roberts, Unnur Thorsteinsdottir, Christopher J O'Donnell, Ruth McPherson, Jeanette Erdmann, Nilesh J Samani.
Nat. Genet.
PUBLISHED: 02-10-2011
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We performed a meta-analysis of 14 genome-wide association studies of coronary artery disease (CAD) comprising 22,233 individuals with CAD (cases) and 64,762 controls of European descent followed by genotyping of top association signals in 56,682 additional individuals. This analysis identified 13 loci newly associated with CAD at P < 5 × 10?? and confirmed the association of 10 of 12 previously reported CAD loci. The 13 new loci showed risk allele frequencies ranging from 0.13 to 0.91 and were associated with a 6% to 17% increase in the risk of CAD per allele. Notably, only three of the new loci showed significant association with traditional CAD risk factors and the majority lie in gene regions not previously implicated in the pathogenesis of CAD. Finally, five of the new CAD risk loci appear to have pleiotropic effects, showing strong association with various other human diseases or traits.
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Mirror extreme BMI phenotypes associated with gene dosage at the chromosome 16p11.2 locus.
Sébastien Jacquemont, Alexandre Reymond, Flore Zufferey, Louise Harewood, Robin G Walters, Zoltan Kutalik, Danielle Martinet, Yiping Shen, Armand Valsesia, Noam D Beckmann, Gudmar Thorleifsson, Marco Belfiore, Sonia Bouquillon, Dominique Campion, Nicole de Leeuw, Bert B A de Vries, Tonu Esko, Bridget A Fernandez, Fernando Fernandez-Aranda, José Manuel Fernández-Real, Mònica Gratacòs, Audrey Guilmatre, Juliane Hoyer, Marjo-Riitta Järvelin, R Frank Kooy, Ants Kurg, Cédric Le Caignec, Katrin Männik, Orah S Platt, Damien Sanlaville, Mieke M van Haelst, Sergi Villatoro Gomez, Faida Walha, Bai-Lin Wu, Yongguo Yu, Azzedine Aboura, Marie-Claude Addor, Yves Alembik, Stylianos E Antonarakis, Benoit Arveiler, Magalie Barth, Nathalie Bednarek, Frédérique Béna, Sven Bergmann, Mylène Beri, Laura Bernardini, Bettina Blaumeiser, Dominique Bonneau, Armand Bottani, Odile Boute, Han G Brunner, Dorothée Cailley, Patrick Callier, Jean Chiesa, Jacqueline Chrast, Lachlan Coin, Charles Coutton, Jean-Marie Cuisset, Jean-Christophe Cuvellier, Albert David, Bénédicte de Freminville, Bruno Delobel, Marie-Ange Delrue, Bénédicte Demeer, Dominique Descamps, Gérard Didelot, Klaus Dieterich, Vittoria Disciglio, Martine Doco-Fenzy, Séverine Drunat, Bénédicte Duban-Bedu, Christèle Dubourg, Julia S El-Sayed Moustafa, Paul Elliott, Brigitte H W Faas, Laurence Faivre, Anne Faudet, Florence Fellmann, Alessandra Ferrarini, Richard Fisher, Elisabeth Flori, Lukas Forer, Dominique Gaillard, Marion Gérard, Christian Gieger, Stefania Gimelli, Giorgio Gimelli, Hans J Grabe, Agnès Guichet, Olivier Guillin, Anna-Liisa Hartikainen, Delphine Heron, Loyse Hippolyte, Muriel Holder, Georg Homuth, Bertrand Isidor, Sylvie Jaillard, Zdenek Jaros, Susana Jiménez-Murcia, Géraldine Joly Helas, Philippe Jonveaux, Satu Kaksonen, Boris Keren, Anita Kloss-Brandstätter, Nine V A M Knoers, David A Koolen, Peter M Kroisel, Florian Kronenberg, Audrey Labalme, Emilie Landais, Elisabetta Lapi, Valérie Layet, Solenn Legallic, Bruno Leheup, Barbara Leube, Suzanne Lewis, Josette Lucas, Kay D MacDermot, Páll Magnússon, Christian Marshall, Michèle Mathieu-Dramard, Mark I McCarthy, Thomas Meitinger, Maria Antonietta Mencarelli, Giuseppe Merla, Alexandre Moerman, Vincent Mooser, Fanny Morice-Picard, Mafalda Mucciolo, Matthias Nauck, Ndeye Coumba Ndiaye, Ann Nordgren, Laurent Pasquier, Florence Petit, Rolph Pfundt, Ghislaine Plessis, Evica Rajcan-Separovic, Gian Paolo Ramelli, Anita Rauch, Roberto Ravazzolo, André Reis, Alessandra Renieri, Cristóbal Richart, Janina S Ried, Claudine Rieubland, Wendy Roberts, Katharina M Roetzer, Caroline Rooryck, Massimiliano Rossi, Evald Saemundsen, Véronique Satre, Claudia Schurmann, Engilbert Sigurdsson, Dimitri J Stavropoulos, Hreinn Stefansson, Carola Tengström, Unnur Thorsteinsdottir, Francisco J Tinahones, Renaud Touraine, Louis Vallée, Ellen van Binsbergen, Nathalie Van der Aa, Catherine Vincent-Delorme, Sophie Visvikis-Siest, Peter Vollenweider, Henry Völzke, Anneke T Vulto-van Silfhout, Gérard Waeber, Carina Wallgren-Pettersson, Robert M Witwicki, Simon Zwolinksi, Joris Andrieux, Xavier Estivill, James F Gusella, Omar Gústafsson, Andres Metspalu, Stephen W Scherer, Kari Stefansson, Alexandra I F Blakemore, Jacques S Beckmann, Philippe Froguel.
Nature
PUBLISHED: 02-09-2011
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Both obesity and being underweight have been associated with increased mortality. Underweight, defined as a body mass index (BMI) ??18.5?kg?per?m(2) in adults and ??-2 standard deviations from the mean in children, is the main sign of a series of heterogeneous clinical conditions including failure to thrive, feeding and eating disorder and/or anorexia nervosa. In contrast to obesity, few genetic variants underlying these clinical conditions have been reported. We previously showed that hemizygosity of a ?600-kilobase (kb) region on the short arm of chromosome 16 causes a highly penetrant form of obesity that is often associated with hyperphagia and intellectual disabilities. Here we show that the corresponding reciprocal duplication is associated with being underweight. We identified 138 duplication carriers (including 132 novel cases and 108 unrelated carriers) from individuals clinically referred for developmental or intellectual disabilities (DD/ID) or psychiatric disorders, or recruited from population-based cohorts. These carriers show significantly reduced postnatal weight and BMI. Half of the boys younger than five years are underweight with a probable diagnosis of failure to thrive, whereas adult duplication carriers have an 8.3-fold increased risk of being clinically underweight. We observe a trend towards increased severity in males, as well as a depletion of male carriers among non-medically ascertained cases. These features are associated with an unusually high frequency of selective and restrictive eating behaviours and a significant reduction in head circumference. Each of the observed phenotypes is the converse of one reported in carriers of deletions at this locus. The phenotypes correlate with changes in transcript levels for genes mapping within the duplication but not in flanking regions. The reciprocal impact of these 16p11.2 copy-number variants indicates that severe obesity and being underweight could have mirror aetiologies, possibly through contrasting effects on energy balance.
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Mutations in the mitochondrial thioredoxin reductase gene TXNRD2 cause dilated cardiomyopathy.
Eur. Heart J.
PUBLISHED: 01-18-2011
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Cardiac energy requirement is met to a large extent by oxidative phosphorylation in mitochondria that are highly abundant in cardiac myocytes. Human mitochondrial thioredoxin reductase (TXNRD2) is a selenocysteine-containing enzyme essential for mitochondrial oxygen radical scavenging. Cardiac-specific deletion of Txnrd2 in mice results in dilated cardiomyopathy (DCM). The aim of this study was to investigate whether TXNRD2 mutations explain a fraction of monogenic DCM cases.
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Genome-wide association studies of atrial fibrillation: past, present, and future.
Cardiovasc. Res.
PUBLISHED: 01-18-2011
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Genome-wide association studies (GWAS) for atrial fibrillation (AF) have identified three distinct genetic loci on chromosomes 1q21, 4q25, and 16q22 that are associated with the arrhythmia. Susceptibility loci also have been identified by GWAS for PR interval duration, a quantitative phenotype related to AF. In this review article, we have sought to summarize the latest findings for population-based genetic studies of AF, to highlight ongoing functional studies, and to explore the future directions of genetic research on AF.
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Cellular rescue-assay aids verification of causative DNA-variants in mitochondrial complex I deficiency.
Mol. Genet. Metab.
PUBLISHED: 01-17-2011
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Mitochondrial complex I deficiency is a frequent biochemical condition, causing about one third of respiratory chain disorders. Partly due to the large number of genes necessary for its assembly and function only a small proportion of complex I deficiencies are yet confirmed at the molecular genetic level. Now, next generation sequencing approaches are applied to close the gap between biochemical definition and molecular diagnosis. Nevertheless such approaches result in a long list of novel rare single nucleotide variants. Identifying the causative mutations still remains challenging. Here we describe the identification and functional confirmation of novel NDUFS1 mutations using a cellular rescue-assay. Patient-derived complex I-defective fibroblast cell lines were transduced with wild type and mutant NDUFS1-cDNA and subsequently analyzed on the functional and protein level. We established the pathogenic nature of identified rare variants in four out of five disease alleles. This approach is a valuable add-on in disease genetics and it allows the analysis of the functional consequences of genetic variants in metabolic disorders.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.