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

Когда сравниваются несколько человеческих геномов, в последовательностях наблюдаются вариации.
Вариации, вызванные заменой одного нуклеотида, называются однонуклеотидными полиморфизмами, или SNP.
Вариации, вызванные вставкой или делецией последовательности нуклеотидов длиной менее одного килооснования, называются инделами.
Если вставка или делеция нуклеотидов копируется переменное количество раз в одном и том же геноме, это называется вариацией числа копий или CNV. Часто CNV включают в себя большие участки ДНК длиной более одного килооснования.
Гаплотип — это набор генов, унаследованных от одного родителя. Геном может быть разделен на блоки гаплотипов, которые содержат кластеры полиморфизмов.
Поскольку во время каждого мейоза между гомологичными хромосомами происходит мало кроссинговеров, гаплотипические блоки наследуются в сцепленной группе из поколения в поколение.

<ol>
	<li>Чанок, Стивен. "Гены-кандидаты и однонуклеотидные полиморфизмы (SNP) в изучении болезней человека." Маркеры болезней 17, No2 (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>Гао, Жунсуй, Вэньхун Цзу, Ян Лю, Цзюньхуа Ли, Цзэяо Ли, Янлин Вэнь, Хайян Ван и др. "Квазивиды SARS-CoV-2, выявленные с помощью анализа однонуклеотидных полиморфизмов (SNP)." Вирулентность 12, No 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>

Однонуклеотидные полиморфизмы-snp

Однонуклеотидный полиморфизм или SNP представляет собой вариацию одного нуклеотида в определенной геномной позиции в большой популяции. Это наиболее распространенный тип вариации последовательности, обнаруженный в геноме человека. Точечные мутации, встречающиеся более чем у 1% населения, квалифицируются как SNP. В среднем в геноме человека они присутствуют каждые 1000 нуклеотидов. Замена пурина другим пурином (A/G) или пиримидина другим пиримидином (C/T) известна как переход. Напротив, замена пурина пиримидином (A, G/C или T) или наоборот называется трансверсией. В SNP переходы более заметны, чем трансверсии. Для изучения генетических вариаций, присутствующих в геноме, используются различные методы, также известные как генотипирование. В отличие от SNP, одиночные тандемные повторы (STR) включают ди-, три- или тетрануклеотидные повторы. Ученые часто используют генотипирование SNP вместо STR, поскольку SNP более распространены и стабильны, а некоторые SNP напрямую влияют на фенотип. Большую часть времени SNP находятся в интронах, которые не кодируют какой-либо белок. Такие SNP можно использовать в качестве биологических маркеров для обнаружения генов, связанных с конкретным заболеванием. Если SNP присутствует внутри гена или в регуляторной последовательности рядом с геном, это может повлиять на его функцию и вызвать заболевание.

Однонуклеотидные полиморфизмы-SNP

Однонуклеотидный полиморфизм или SNP — это вариация одного нуклеотида в определенной геномной позиции в большой популяции. Он является наиболее распространенным ...

Education

JoVE Core

Molecular Biology

Молекулярная биология

Unit 2

Раздел 2

Analyzing Gene Expression and Function

Анализ экспрессии и функций генов

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

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-snps

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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transgenic plants

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gene therapy

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epistasis analysis

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genome-wide association studies-gwas

Using SNP Patterns to Link Disease Risk

Genome-wide association studies, or GWAS, look for common SNPs, or single nucleotide polymorphisms, that may be linked to disease. Researchers compare how often a SNP appears in people with a disease and in people without it. When a SNP is seen more often in the disease group, it is considered associated with that disease. GWAS uses chi-square analysis to test the chance that an allele is linked to the disease. This approach does not require scientists to first find the target gene behind the...

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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