JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Set-based joint test of interaction between SNPs in the VEGF pathway and exogenous estrogen finds association with age-related macular degeneration.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 07-13-2014
Show Abstract
Hide Abstract
Purpose:Age-Related Macular Degeneration (AMD) is the leading cause of irreversible visual loss in developed countries. Its etiology includes genetic and environmental factors. Although VEGFA variants are associated with AMD, the joint action of variants within the VEGF pathway and their interaction with non-genetic factors has not been investigated. Methods:Affymetrix 6.0 chipsets were used to genotype 668,238 SNPs in 1,207 AMD cases and 686 controls. Environmental exposures were collected by questionnaire. A set-based test was conducted using the chi-square statistic at each SNP derived from Kraft's 2df joint test. Pathway and gene-based test statistics were calculated as the mean of all independent SNP statistics. Phenotype labels were permuted 10,000 times to generate an empirical p-value. Results: While a main effect of the VEGF pathway was not identified, the pathway was associated with neovascular AMD in women when accounting for birth control pill (BCP) use (P= 0.017). Analysis of VEGF's subpathways found that SNPs in the Proliferation subpathway were associated with neovascular AMD (P=0.029) when accounting for BCP use. Nominally significant genes within this subpathway were also observed. Stratification by BCP use revealed novel significant genetic effects in women who had taken BCPs. Conclusions: These results illustrate that some AMD genetic risk factors may only be revealed when considering complex relationships among risk factors. This shows the utility of exploring pathways of previously associated genes to find novel effects. It also demonstrates the importance of incorporating environmental exposures in tests of genetic association at the SNP, gene, or pathway level.
Related JoVE Video
Rare complement factor H variant associated with age-related macular degeneration in the Amish.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 06-08-2014
Show Abstract
Hide Abstract
Age-related macular degeneration is the leading cause of blindness among the adult population in the developed world. To further the understanding of this disease, we have studied the genetically isolated Amish population of Ohio and Indiana.
Related JoVE Video
UV-independent p53 mutations in sebaceous carcinoma of the eyelid.
Ophthal Plast Reconstr Surg
PUBLISHED: 04-30-2014
Show Abstract
Hide Abstract
Sebaceous carcinoma of the eyelid is a potentially fatal malignancy that has been associated with p53 gene mutations. The purpose of this study is to determine the frequency of p53 mutations in sebaceous carcinoma of the eyelid and to determine whether there is any relationship between the presence of p53 mutations and tumor invasiveness.
Related JoVE Video
Comparative transcriptome analysis of two races of Heterodera glycines at different developmental stages.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The soybean cyst nematode, Heterodera glycines, is an important pest of soybeans. Although resistance is available against this nematode, selection for virulent races can occur, allowing the nematode to overcome the resistance of cultivars. There are abundant field populations, however, little is known about their genetic diversity. In order to elucidate the differences between races, we investigated the transcriptional diversity within race 3 and race 4 inbred lines during their compatible interactions with the soybean host Zhonghuang 13. Six different race-enriched cDNA libraries were constructed with limited nematode samples collected from the three sedentary stages, parasitic J2, J3 and J4 female, respectively. Among 689 putative race-enriched genes isolated from the six libraries with functional annotations, 92 were validated by quantitative RT-PCR (qRT-PCR), including eight putative effector encoding genes. Further race-enriched genes were validated within race 3 and race 4 during development in soybean roots. Gene Ontology (GO) analysis of all the race-enriched genes at J3 and J4 female stages showed that most of them functioned in metabolic processes. Relative transcript level analysis of 13 selected race-enriched genes at four developmental stages showed that the differences in their expression abundance took place at either one or more developmental stages. This is the first investigation into the transcript diversity of H. glycines races throughout their sedentary stages, increasing the understanding of the genetic diversity of H. glycines.
Related JoVE Video
Chromosome 10q26 locus and age-related macular degeneration: A progress update.
Exp. Eye Res.
PUBLISHED: 09-11-2013
Show Abstract
Hide Abstract
Age-related macular degeneration (AMD) is the leading cause of late-onset central vision loss in developed countries. Both genetic and environmental factors contribute to the onset of AMD. Variation at a locus on chromosome 10q26 has been consistently associated with this disease and represents one of the two strongest genetic effects being identified in AMD. At least three genes are located within the bounds of the locus: pleckstrin homology domain containing family A member 1 (PLEKHA1), age-related maculopathy susceptibility 2 (ARMS2) and high-temperature requirement A serine peptidase 1 (HTRA1), all of which are associated with AMD. Due to the strong linkage disequilibrium (LD) across this region, statistical genetic analysis alone is incapable of distinguishing the effect of an individual gene in the locus. Uncertainty remains, however, in regards to which gene is responsible for the linkage and association of the locus with AMD. Investigating functional consequences of the associated variants and related genes tends to be essential to identifying the biologically responsible gene(s) underlying AMD. This review examines the recent progress and current uncertainty on the genetic and functional analyses of the 10q26 locus in AMD with a focus on ARMS2 and HTRA1. A discussion, which entails the possible multi-faceted approaches for pinpointing the gene(s) in the locus underlying the pathogenesis of AMD, is also included.
Related JoVE Video
Ascorbate-induced generation of 5-hydroxymethylcytosine is unaffected by varying levels of iron and 2-oxoglutarate.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-29-2013
Show Abstract
Hide Abstract
Tet (ten-eleven translocation) methylcytosine dioxygenases, which belong to the iron and 2-oxoglutarate (2OG)-dependent dioxygenase superfamily, convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) in DNA. We recently reported that ascorbate (vitamin C) induces Tet-mediated generation of 5hmC. To initially delineate the role of ascorbate on 5hmC generation, we analyzed whether the effect of ascorbate is dependent upon the conditions of other components involved in the hydroxylation of 5mC catalyzed by Tet. We found that removing iron from the culture medium did not affect the induction of 5hmC by ascorbate (10 ?M) in mouse embryonic fibroblasts (MEFs). The effect of ascorbate did not involve an increased expression of Tet1-3 or isocitrate dehydrogenases (IDH1-2), the enzymes responsible for producing 2OG. Interestingly, MEFs cultured with different concentrations of glucose, a major precursor of 2OG, exhibited nearly identical responses to ascorbate treatment. Further, blocking the uptake of the reduced form of vitamin C, ascorbic acid, through the sodium-dependent vitamin C transporters (SVCTs) inhibited the effect of ascorbate on 5hmC. However, inhibition of the facilitative glucose transporters (GLUTs), which mediate the incorporation of the oxidized form of vitamin C, dehydroascorbic acid (DHA), did not modify the ability of ascorbate to induce 5hmC generation. These results indicate that the effect of ascorbate on 5hmC is not dependent upon iron uptake, the expression of Tet and IDH, or the production of 2OG, suggesting that ascorbate may directly participate in the generation of 5hmC, most likely as a cofactor of Tet.
Related JoVE Video
AMD-associated variants at the chromosome 10q26 locus and the stability of ARMS2 transcripts.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 08-15-2013
Show Abstract
Hide Abstract
To analyze the effect of variants including age-related macular degeneration (AMD)-associated combinative insertion/deletion polymorphism (indel) at 3UTR of ARMS2 and possibly associated R38X on the stability of ARMS2 transcripts.
Related JoVE Video
Anxiety and adverse coronary artery disease outcomes in Chinese patients.
Psychosom Med
PUBLISHED: 06-20-2013
Show Abstract
Hide Abstract
To investigate the impact of anxiety on the prognosis of coronary artery disease (CAD) in patients of Chinese Han ethnicity and to explore the correlation between anxiety and the severity of coronary atherosclerosis.
Related JoVE Video
Variants at chromosome 10q26 locus and the expression of HTRA1 in the retina.
Exp. Eye Res.
PUBLISHED: 04-19-2013
Show Abstract
Hide Abstract
Variations in a locus at chromosome 10q26 are strongly associated with the risk of age-related macular degeneration (AMD). The most significantly associated haplotype includes a nonsynonymous SNP rs10490924 in the exon 1 of ARMS2 and rs11200638 in the promoter region of HTRA1. It is under debate which gene(s), ARMS2, HTRA1 or some other genes are functionally responsible for the genetic association. To verify whether the associated variants correlate with a higher HTRA1 expression level as previously reported, HTRA1 mRNA and protein were measured in a larger human retina-RPE-choroid samples (n = 82). Results show there is no significant change of HTRA1 mRNA level among genotypes at rs11200638, rs10490924 or an indel variant of ARMS2. Furthermore, two AMD-associated synonymous SNPs rs1049331 and rs2293870 in HTRA1 exon 1 do not change its protein level either. These results suggest that the AMD-associated variants in the chromosome 10q26 locus do not significantly affect the expression of HTRA1.
Related JoVE Video
Genetic factors in nonsmokers with age-related macular degeneration revealed through genome-wide gene-environment interaction analysis.
Ann. Hum. Genet.
PUBLISHED: 04-13-2013
Show Abstract
Hide Abstract
Relatively little is known about the interaction between genes and environment in the complex etiology of age-related macular degeneration (AMD). This study aimed to identify novel factors associated with AMD by analyzing gene-smoking interactions in a genome-wide association study of 1207 AMD cases and 686 controls of Caucasian background with genotype data on 668,238 single nucleotide polymorphisms (SNPs) after quality control. Participants history of smoking at least 100 cigarettes lifetime was determined by a self-administered questionnaire. SNP associations modeled the effect of the minor allele additively on AMD using logistic regression, with adjustment for age, sex, and ever/never smoking. Joint effects of SNPs and smoking were examined comparing a null model containing only age, sex, and smoking against an extended model including genotypic and interaction terms. Genome-wide significant main effects were detected at three known AMD loci: CFH (P = 7.51×10(-30) ), ARMS2 (P = 1.94×10(-23) ), and RDBP/CFB/C2 (P = 4.37×10(-10) ), while joint effects analysis revealed three genomic regions with P < 10(-5) . Analyses stratified by smoking found genetic associations largely restricted to nonsmokers, with one notable exception: the chromosome 18q22.1 intergenic SNP rs17073641 (between SERPINB8 and CDH7), more strongly associated in nonsmokers (OR = 0.57, P = 2.73 × 10(-5) ), with an inverse association among smokers (OR = 1.42, P = 0.00228), suggesting that smoking modifies the effect of some genetic polymorphisms on AMD risk.
Related JoVE Video
Ascorbate induces ten-eleven translocation (Tet) methylcytosine dioxygenase-mediated generation of 5-hydroxymethylcytosine.
J. Biol. Chem.
PUBLISHED: 04-02-2013
Show Abstract
Hide Abstract
Tet methylcytosine dioxygenase converts 5-mC to 5-hmC in DNA.
Related JoVE Video
Analysis of the dynamic relationships between the lingual artery and lingual markers in patients with obstructive sleep apnea.
Surg Radiol Anat
PUBLISHED: 01-05-2013
Show Abstract
Hide Abstract
To determine the relationships between the lingual artery and the lingual markers in tongue resting and extended positions in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) for the clinical application of functional tongue surgery.
Related JoVE Video
Next-generation sequencing of mitochondrial targeted AAV transfer of human ND4 in mice.
Mol. Vis.
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
To determine the effects of mitochondrial targeting sequence (MTS) modified AAV gene delivery of wild-type human NADH dehydrogenase subunit 4 (ND4), mutated in most cases of the blinding disease Leber hereditary optic neuropathy (LHON), on the host mouse mitochondrial genome.
Related JoVE Video
[Cloning and sequence analysis of a new cathepsin L-like cysteine proteinase gene from Ditylenchus destructor].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 05-11-2011
Show Abstract
Hide Abstract
The Cathepsin L-like cysteine proteinase genes (cpls) are multifunction genes related to the parasitic abilities of plant parasitic nematodes. A new cathepsin L-like cysteine proteinase gene (Dd-cpl-1) (GenBank Accession GQ 180107) was cloned from Ditylenchus destructor by RT-PCR and RACE. The cDNA sequence consisted of a 1 131 bp open reading frame (ORF) encoding 376 amino acid residues that were franked by a 29 bp 5-untranslated region (UTR) and a 159 bp 3-UTR. Genomic sequence analysis showed that Dd-cpl-1 contained 7 introns, obeyed the GT/AG rule in the splice-site junctions. Homology analysis showed that the identity was 77% between Dd-cpl-1 deduced protein Dd-CPL-1 and cathepsin L-like cysteine proteinase of Bursaphelenchus xylophilus. Multi-sequence alignment indicated that there were the catalytic triad (Cys183, His322 and Asn343) and two motifs ERFNIN motif and GNFD motif in deduced protein Dd-CPL-1. Cysteine proteinases phylogenetic analysis showed that Dd-cpl-1 belonged to the sub-clade of cathepsin L-like cysteine proteinases.
Related JoVE Video
S-nitrosylation of ApoE in Alzheimers disease.
Biochemistry
PUBLISHED: 04-06-2011
Show Abstract
Hide Abstract
The mechanism by which apolipoprotein E (ApoE) isoforms functionally influence the risk and progression of late-onset Alzheimers disease (LOAD) remains hitherto unknown. Herein, we present evidence that all ApoE isoforms bind to nitric oxide synthase 1 (NOS1) and that such protein-protein interaction results in S-nitrosylation of ApoE2 and ApoE3 but not ApoE4. Our structural analysis at the atomic level reveals that S-nitrosylation of ApoE2 and ApoE3 proteins may lead to conformational changes resulting in the loss of binding to low-density lipoprotein (LDL) receptors. Collectively, our data suggest that S-nitrosylation of ApoE proteins may play an important role in regulating lipid metabolism and in the pathogenesis of LOAD.
Related JoVE Video
Dynamin2- and endothelial nitric oxide synthase-regulated invasion of bladder epithelial cells by uropathogenic Escherichia coli.
J. Cell Biol.
PUBLISHED: 01-12-2011
Show Abstract
Hide Abstract
Invasion of bladder epithelial cells by uropathogenic Escherichia coli (UPEC) contributes to antibiotic-resistant and recurrent urinary tract infections (UTIs), but this process is incompletely understood. In this paper, we provide evidence that the large guanosine triphosphatase dynamin2 and its partner, endothelial nitric oxide (NO) synthase (NOS [eNOS]), mediate bacterial entry. Overexpression of dynamin2 or treatment with the NO donor S-nitrosothiols increases, whereas targeted reduction of endogenous dynamin2 or eNOS expression with ribonucleic acid interference impairs, bacterial invasion. Exposure of mouse bladder to small molecule NOS inhibitors abrogates infection of the uroepithelium by E. coli, and, concordantly, bacteria more efficiently invade uroepithelia isolated from wild-type compared with eNOS(-/-) mice. E. coli internalization promotes rapid phosphorylation of host cell eNOS and NO generation, and dynamin2 S-nitrosylation, a posttranslational modification required for the bacterial entry, also increases during E. coli invasion. These findings suggest that UPEC escape urinary flushing and immune cell surveillance by means of eNOS-dependent dynamin2 S-nitrosylation and invasion of host cells to cause recurrent UTIs.
Related JoVE Video
Dissection of chromosome 16p12 linkage peak suggests a possible role for CACNG3 variants in age-related macular degeneration susceptibility.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-01-2011
Show Abstract
Hide Abstract
Age-related macular degeneration (AMD) is a complex disorder of the retina, characterized by drusen, geographic atrophy, and choroidal neovascularization. Cigarette smoking and the genetic variants CFH Y402H, ARMS2 A69S, CFB R32Q, and C3 R102G have been strongly and consistently associated with AMD. Multiple linkage studies have found evidence suggestive of another AMD locus on chromosome 16p12 but the gene responsible has yet to be identified.
Related JoVE Video
Analysis of single nucleotide polymorphisms in the NOS2A gene and interaction with smoking in age-related macular degeneration.
Ann. Hum. Genet.
PUBLISHED: 03-31-2010
Show Abstract
Hide Abstract
Age-related macular degeneration (AMD) is a complex degenerative retinal disease influenced by both genetic and environmental risk factors. We assessed whether single nucleotide polymorphisms (SNPs) in the NOS2A gene increase risk and modulate the effect of smoking in AMD. 998 Caucasian subjects (712 AMD cases and 286 controls) were genotyped for 17 SNPs in NOS2A. Multivariable logistic regression models containing SNP genotypes, age, sex, smoking status and genotype/smoking interaction were constructed. SNP rs8072199 was significantly associated with AMD (OR = 1.3; 95% CI : 1.02, 1.65; P = 0.035). A significant interaction with smoking was detected at rs2248814 (P = 0.037). Stratified data by genotypes demonstrated that the association between AMD and smoking was stronger in carriers of AA genotypes (OR = 35.98; 95% CI: 3.19, 405.98) than in carriers of the AG genotype (OR = 3.05; 95% CI: 1.36, 6.74) or GG genotype (OR = 2.1; 95% CI: 0.91, 4.84). The results suggest a possible synergistic interaction of AA genotype with smoking, although the result bears replication in larger samples. Our data suggests that SNPs in the NOS2A gene are associated with increased risk for AMD and might modulate the effect of smoking on AMD.
Related JoVE Video
Analysis of the indel at the ARMS2 3UTR in age-related macular degeneration.
Hum. Genet.
PUBLISHED: 02-12-2010
Show Abstract
Hide Abstract
Controversy remains as to which gene at the chromosome 10q26 locus confers risk for age-related macular degeneration (AMD) and statistical genetic analysis is confounded by the strong linkage disequilibrium (LD) across the region. Functional analysis of related genetic variations could solve this puzzle. Recently, Fritsche et al. reported that AMD is associated with unstable ARMS2 transcripts possibly caused by a complex insertion/deletion (indel; consisting of a 443 bp deletion and an adjacent 54 bp insertion) in its 3UTR (untranslated region). To validate this indel, we sequenced our samples. We found that this indel is even more complex and is composed of two side-by-side indels separated by 17 bp: (1) 9 bp deletion with 10 bp insertion; (2) 417 bp deletion with 27 bp insertion. The indel is significantly associated with the risk of AMD, but is also in strong LD with the non-synonymous single nucleotide polymorphism rs10490924 (A69S). We also found that ARMS2 is expressed not only in placenta and retina but also in multiple human tissues. Using quantitative PCR, we found no correlation between the indel and ARMS2 mRNA level in human retina and blood samples. The lack of functional effects of the 3UTR indel, the amino acid substitution of rs10490924 (A69S), and strong LD between them suggest that A69S, not the indel, is the variant that confers risk of AMD. To our knowledge, it is the first time it has been shown that ARMS2 is widely expressed in human tissues. Conclusively, the indel at 3UTR of ARMS2 actually contains two side-by-side indels. The indels are associated with risk of AMD, but not correlated with ARMS2 mRNA level.
Related JoVE Video
High-overtone self-focusing acoustic transducers for high-frequency ultrasonic Doppler.
Ultrasonics
PUBLISHED: 01-26-2010
Show Abstract
Hide Abstract
This work reports the potential use of high-overtone self-focusing acoustic transducers for high-frequency ultrasonic Doppler. By using harmonic frequencies of a thick bulk Lead Zirconate Titanate (PZT) transducer with a novel air-reflector Fresnel lens, we obtained strong ultrasound signals at 60 MHz (3rd harmonic) and 100 MHz (5th harmonic). Both experimental and theoretical analysis has demonstrated that the transducers can be applied to Doppler systems with high frequencies up to 100 MHz.
Related JoVE Video
Genome-wide association study confirms SNPs in SNCA and the MAPT region as common risk factors for Parkinson disease.
Ann. Hum. Genet.
PUBLISHED: 01-08-2010
Show Abstract
Hide Abstract
Parkinson disease (PD) is a chronic neurodegenerative disorder with a cumulative prevalence of greater than one per thousand. To date three independent genome-wide association studies (GWAS) have investigated the genetic susceptibility to PD. These studies implicated several genes as PD risk loci with strong, but not genome-wide significant, associations. In this study, we combined data from two previously published GWAS of Caucasian subjects with our GWAS of 604 cases and 619 controls for a joint analysis with a combined sample size of 1752 cases and 1745 controls. SNPs in SNCA (rs2736990, p-value = 6.7 x 10(-8); genome-wide adjusted p = 0.0109, odds ratio (OR) = 1.29 [95% CI: 1.17-1.42] G vs. A allele, population attributable risk percent (PAR%) = 12%) and the MAPT region (rs11012, p-value = 5.6 x 10(-8); genome-wide adjusted p = 0.0079, OR = 0.70 [95% CI: 0.62-0.79] T vs. C allele, PAR%= 8%) were genome-wide significant. No other SNPs were genome-wide significant in this analysis. This study confirms that SNCA and the MAPT region are major genes whose common variants are influencing risk of PD.
Related JoVE Video
Design and fabrication of PIN-PMN-PT single-crystal high-frequency ultrasound transducers.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 12-31-2009
Show Abstract
Hide Abstract
High-frequency PIN-PMN-PT single crystal ultrasound transducers at center frequencies of 35 MHz and 60 MHz were successfully fabricated using lead indium niobate-lead magnesium niobate-lead titanate (0.23PIN- 0.5PMN-0.27PT) single crystal. The new PIN-PMN-PT single crystal has higher coercivity (6.0 kV/cm) and higher Curie temperature (160 degrees C) than PMN-PT crystal. Experimental results showed that the PIN-PMN-PT transducers have similar performance but better thermal stability compared with the PMN-PT transducers.
Related JoVE Video
Functional evidence implicating a novel TOR1A mutation in idiopathic, late-onset focal dystonia.
J. Med. Genet.
PUBLISHED: 12-02-2009
Show Abstract
Hide Abstract
TOR1A encodes a chaperone-like AAA-ATPase whose Delta GAG (Delta E) mutation is responsible for an early onset, generalised dystonia syndrome. Because of the established role of the TOR1A gene in heritable generalised dystonia (DYT1), a potential genetic contribution of TOR1A to the more prevalent and diverse presentations of late onset, focal dystonia has been suggested.
Related JoVE Video
Inverse association of female hormone replacement therapy with age-related macular degeneration and interactions with ARMS2 polymorphisms.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-20-2009
Show Abstract
Hide Abstract
Purpose. To investigate whether female reproductive history and hormone replacement therapy (HRT) or birth control pills (BCPs) influence risk for age-related macular degeneration (AMD) and whether genetic factors interact with HRT to modulate AMD risk. Methods. Related and unrelated female participants (n = 799) were examined and data were analyzed with generalized estimating equations with adjustment for age and smoking. Individuals with AMD grades 1 to 2 were considered to be unaffected (n = 239) and those with grades 3 to 5 were considered affected (n = 560). Results. When comparing all cases with controls, significant inverse associations were observed for HRT (odds ratio [OR] = 0.65, 95% CI 0.48-0.90, P = 0.008) and BCPs (OR = 0.60, 95% CI 0.36-0.10, P = 0.048). When analyses were stratified by AMD severity (early versus geographic atrophy versus neovascular), the inverse association remained significant (HRT OR = 0.45, 95% CI 0.30-0.66, P < 0.0001; BCP OR = 0.55, 95% CI 0.32-0.96, P = 0.036) only when comparing neovascular AMD with the control. All pair-wise HRT-genotype and BCP-genotype interactions were examined, to determine whether HRT or BCP modifies the effect of established genetic risk factors. The strongest interactions were observed for HRT x ARMS2 coding SNP (R73H) rs10490923 (P = 0.007) and HRT x ARMS2 intronic SNP rs17623531 (P = 0.019). Conclusions. These findings provide the first evidence suggesting that ARMS2 interacts with HRT to modulate AMD risk and are consistent with previous reports demonstrating a protective relationship between exogenous estrogen use and neovascular AMD. These results highlight the genetic and environmental complexity of the etiologic architecture of AMD; however, further replication is necessary to validate them.
Related JoVE Video
Copy number variations are a rare cause of non-CMT1A Charcot-Marie-Tooth disease.
J. Neurol.
PUBLISHED: 10-09-2009
Show Abstract
Hide Abstract
Hereditary peripheral neuropathies present a group of clinically and genetically heterogeneous entities. All known forms, including the various forms of Charcot-Marie-Tooth disease (CMT) are characterized as Mendelian traits and over 35 genes have been identified thus far. The mutational mechanism of the most common CMT type, CMT1A, is a 1.5 Mb chromosomal duplication at 17p12 that contains the gene PMP22. Only recently it has been realized that such copy number variants (CNV) are a widespread phenomenon and important for disease. However, it is not known whether CNVs play a wider role in hereditary peripheral neuropathies outside of CMT1A. In a phenotypically heterogeneous sample of 97 patients, we performed the first high-density CNV study of 34 genomic regions harboring known genes for hereditary peripheral neuropathies including the 17p12 duplication region, with comparative genomic hybridization (CGH) microarrays. We identified three CNVs that affected coding exons. A novel shorter form of a PMP22 duplication was detected in a CMT1A family previously tested negative in a commercial test. Two other CNVs in MTMR2 and ARHGEF10 are likely not disease associated. Our results indicate that CNVs are a rare cause for non-CMT1A CMT. Their potential relevance as disease modifiers remains to be evaluated. The present study design cannot rule out that specific CMT forms exist where CNVs play a larger role.
Related JoVE Video
Localization of age-related macular degeneration-associated ARMS2 in cytosol, not mitochondria.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 02-28-2009
Show Abstract
Hide Abstract
To analyze the relationship between ARMS2 and HTRA1 in the association with age-related macular degeneration (AMD) in an independent case-control dataset and to investigate the subcellular localization of the ARMS2 protein in an in vitro system.
Related JoVE Video
Effects of the inhomogenous co doping on the magnetoresistance of Zn1-xCo(x)O epitaxial films.
J Nanosci Nanotechnol
Show Abstract
Hide Abstract
A series of Zn1-xCo(x)O epitaxial films around 100 nm with nominal Co concentration from 5% to 15% was prepared by ultra high vacuum (UHV) magnetron reactive sputtering. The optical, magnetic and magneto-transport properties of this series of Zn1-xCo(x)O epitaxial films were investigated, respectively. Resonant Raman spectra indicate the high structural and crystalline quality of these Zn1-xCo(x)O (5 < or = x < or = 15%) films, and confirm a consistent correlation between the substituting Co ions content with the Co doping concentration as well. Paramagnetism, superparamagnetism and ferromagnetism with altered Curie temperature from low temperatures to above room temperatures have been observed in these films by SQUID magnetometry. The broad blocking temperature range indicates the presence of inhomogenous distribution of the magnetic nano-clusters in the superparamagnetic films. However, the magneto-transport behaviors do not strongly respond to the change of the magnetic properties from paramagnetism to ferromagnetism of these Zn1-xCo(x)O films. The lack of efficient coupling between the inhomogenous magnetic nanoclusters and the carrier system in ferromagnetic Zn1-xCo(x)O films highlights the absence of the intrinsic magnetic origins in high structural quality Zn1-xCo(x)O (5 < or = x < or = 15%) epitaxial films. On the other hand, the competition between the spin alignments and the inhomogenous local disorder effect by magnetic ions is suggested to be responsible for the carrier properties and the oberseved magnetoresistance in these Co doping Zn1-xCo(x)O (5 < or = x < or = 15%) epitaxial films.
Related JoVE Video
The ARMS2 A69S variant and bilateral advanced age-related macular degeneration.
Retina (Philadelphia, Pa.)
Show Abstract
Hide Abstract
To identify genetic associations between specific risk genes and bilateral advanced age-related macular degeneration (AMD) in a retrospective, observational case series of 1,003 patients: 173 patients with geographic atrophy in at least 1 eye and 830 patients with choroidal neovascularization in at least 1 eye.
Related JoVE Video
Vitamin D receptor and Alzheimers disease: a genetic and functional study.
Neurobiol. Aging
Show Abstract
Hide Abstract
Genetic studies on late-onset Alzheimers disease (AD) have repeatedly mapped susceptibility loci onto chromosome 12q13, encompassing the vitamin D receptor (VDR) gene. Epidemiology studies have indicated vitamin D insufficiency as a risk factor for AD. Given that VDR is the major mediator for vitamin Ds actions, we sought to clarify the role of VDR in late-onset AD. We conducted an association study in 492 late-onset AD cases and 496 controls with 80 tagging single nucleotide polymorphisms (SNPs). The strongest association was found at a promoter SNP rs11568820 (P = 9.1 × 10(-6), odds ratio (OR) = 1.69), which resides within the transcription factor Cdx-2 binding site and the SNP has been also known as CDX2. The risk-allele at rs11568820 is associated with lower VDR promoter activity (p < 10(-11)). The overexpression of VDR or vitamin D treatment suppressed amyloid precursor protein (APP) transcription in neuroblastoma cells (p < 0.001). We provide both statistical evidence and functional data suggesting VDR confers genetic risk for AD. Our findings are consistent with epidemiology studies suggesting that vitamin D insufficiency increases the risk of developing AD.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

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.