Name: snps as genetic markers and variants
Uploaded: 2021-04-07T12:12:00.000Z
Duration: 1 min 5 s
Channel: JoVE
Description: Single nucleotide polymorphisms, or SNPs, are small DNA changes at one specific genomic position. They are the most common type of sequence variation in the human genome. A point mutation counts as an SNP when it appears in more than 1% of the population.

K12 Standards

Arizona Science Standards

High School

Life Science

HS.L3

HS.L3U3.26

Single Nucleotide Polymorphisms-SNPs

Wenn mehrere menschliche Genome verglichen werden, werden Variationen in den Sequenzen beobachtet.
Variationen aufgrund der Substitution eines Nukleotids werden als Einzelnukleotid-Polymorphismen oder SNPs bezeichnet.
Variationen aufgrund der Insertion oder Deletion einer Sequenz von Nukleotiden mit einer Länge von weniger als einer Kilobase werden als Indel bezeichnet.
Wenn eine Insertion oder Deletion von Nukleotiden eine variable Anzahl von Malen im selben Genom kopiert wird, spricht man von einer Kopienzahlvariation oder CNV. Oft handelt es sich bei CNVs um große DNA-Abschnitte, die mehr als eine Kilobase lang sind.
Ein Haplotyp ist eine Reihe von Genen, die von einem einzigen Elternteil geerbt wurden. Ein Genom kann in Haplotyp-Blöcke unterteilt werden, die Cluster von Polymorphismen enthalten.
Da bei jeder Meiose nur wenige Kreuzungen zwischen homologen Chromosomen auftreten, wurden Haplotyp-Blöcke in einer verknüpften Gruppe über Generationen hinweg vererbt.

<ol>
	<li>Chanock, Stephen. "Kandidatengene und Einzelnukleotid-Polymorphismen (SNPs) bei der Erforschung menschlicher Krankheiten." Krankheitsmarker 17, Nr. 2 (2001): 89-98. <a href="https://downloads.hindawi.com/journals/dm/2001/858760.pdf">https://downloads.hindawi.com/journals/dm/2001/858760.pdf</a></li>
	<li>Gao, Rongsui, Wenhong Zu, Yang Liu, Junhua Li, Zeyao Li, Yanling Wen, Haiyan Wang et al. "Quasispezies von SARS-CoV-2 durch Analyse von Einzelnukleotid-Polymorphismen (SNPs) aufgedeckt." Virulenz 12, Nr. 1 (2021): 1209-1226. <a href="https://www.tandfonline.com/doi/full/10.1080/21505594.2021.1911477">https://www.tandfonline.com/doi/full/10.1080/21505594.2021.1911477</a></li>
</ol>

einzelnukleotid-polymorphismen (snps)

Ein Einzelnukleotid-Polymorphismus oder SNP ist eine Variation eines einzelnen Nukleotids an einer spezifischen genomischen Position in einer großen Population. Es ist die am häufigsten vorkommende Art von Sequenzvariation im menschlichen Genom. Punktmutationen, die bei mehr als 1% der Bevölkerung auftreten, gelten als SNPs. Diese sind durchschnittlich einmal alle 1000 Nukleotide im menschlichen Genom vorhanden. Der Austausch eines Purins durch ein anderes Purin (A/G) oder eines Pyrimidins durch ein anderes Pyrimidin (C/T) wird als Transition bezeichnet. Im Gegensatz dazu wird der Ersatz eines Purins durch ein Pyrimidin (A oder G/C oder T) oder umgekehrt als Transversion bezeichnet. Bei SNPs sind Transitionen häufiger als Transversionen.

Verschiedene Methoden werden verwendet, um die genetischen Variationen im Genom zu studieren, auch als Genotypisierung bekannt. Im Gegensatz zu SNPs beinhalten einfache Tandemwiederholungen (STRs) di-, tri- oder tetranukleotidische Wiederholungen. Wissenschaftler nutzen oft die SNP-Genotypisierung anstelle von STRs, da SNPs häufiger und stabiler sind und einige SNPs direkt den Phänotyp beeinflussen.

Die meisten SNPs befinden sich in Introns, die kein Protein kodieren. Solche SNPs können als biologische Marker verwendet werden, um Gene zu lokalisieren, die mit einer bestimmten Krankheit in Verbindung stehen. Befindet sich der SNP innerhalb eines Gens oder in einer regulatorischen Sequenz in der Nähe des Gens, kann dies dessen Funktion beeinflussen und Krankheiten verursachen.

Einzelnukleotid-Polymorphismen (SNPs)

Ein Einzelnukleotid-Polymorphismus oder SNP ist eine Einzelnukleotidvariation an einer bestimmten genomischen Position in einer großen Population. Es ist die am weitesten verbreitete ...

Education

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Molecular Biology

Molekularbiologie

Unit 2

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Analyzing Gene Expression and Function

Analyse von Genexpression und -funktion

KEY TERMS AND CONCEPTS

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snps as genetic markers and variants

Single nucleotide polymorphisms, or SNPs, are small DNA changes at one specific genomic position. They are the most common type of sequence variation in the human genome. A point mutation counts as an SNP when it appears in more than 1% of the population.

SNPs as Genetic Markers and Variants

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Single nucleotide polymorphisms, or SNPs, are small DNA changes at one specific genomic position. They are the most common type of sequence variation in the human genome. A point mutation counts as an SNP when it appears in more than 1% of the population.

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key terms and concepts

Explore SNPs as common DNA variants, including transitions, transversions, and how they help scientists find genes linked to disease.

SNPs as Genetic Markers and Variants | JoVE K12

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SNPs as Genetic Markers and Variants

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