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

Cuando se comparan múltiples genomas humanos, se observan variaciones en las secuencias.
Las variaciones debidas a la sustitución de un nucleótido se denominan polimorfismos de un solo nucleótido o SNP.
Las variaciones debidas a la inserción o deleción de una secuencia de nucleótidos de menos de una kilobase de longitud se denominan indel.
Si una inserción o deleción de nucleótidos se copia un número variable de veces en el mismo genoma, se denomina variación del número de copias o CNV. A menudo, las CNV involucran grandes tramos de ADN de más de una kilobase de longitud.
Un haplotipo es un conjunto de genes heredados de un solo progenitor. Un genoma se puede dividir en bloques de haplotipos que contienen grupos de polimorfismos.
Dado que se producen pocos entrecruzamientos entre cromosomas homólogos durante cada meiosis, los bloques de haplotipos se han heredado en un grupo vinculado a través de generaciones.

<ol>
	<li>Chanock, Stephen. "Genes candidatos y polimorfismos de un solo nucleótido (SNP) en el estudio de enfermedades humanas". Marcadores de enfermedad 17, no. 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. "Cuasiespecies de SARS-CoV-2 reveladas por análisis de polimorfismos de un solo nucleótido (SNP)". Virulencia 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>

polimorfismos de nucleótido único (snp)

Un polimorfismo de un solo nucleótido o SNP es una variación de un solo nucleótido en una posición genómica específica en una población grande. Es el tipo de variación de secuencia más frecuente que se encuentra en el genoma humano. Las mutaciones puntuales que ocurren en más del 1% de la población califican como SNP. Estos están presentes en promedio una vez cada 1.000 nucleótidos en el genoma humano. La sustitución de una purina por otra purina (A/G) o de una pirimidina por otra pirimidina (C/T) se conoce como transición. Por el contrario, la sustitución de una purina por una pirimidina (A o G/C o T) o viceversa se denomina transversión. En los SNP, las transiciones son más prominentes que las transversiones.

Se utilizan diferentes métodos para estudiar las variaciones genéticas presentes en el genoma, también conocido como genotipado. A diferencia de los SNP, las repeticiones simples en tándem (STR) implican repeticiones de di, tri o tetranucleótidos. Los científicos suelen utilizar el genotipado de SNP en lugar de STR, ya que los SNP son más abundantes y estables, y algunos SNP afectan directamente el fenotipo.

La mayoría de las veces, los SNP se encuentran en intrones, que no codifican ninguna proteína. Estos SNP se pueden utilizar como marcadores biológicos para localizar genes asociados con una enfermedad particular. Si el SNP está presente dentro de un gen o en una secuencia reguladora cerca del gen, puede afectar su función y causar enfermedad.

Polimorfismos de nucleótido único (SNP)

Un polimorfismo de un solo nucleótido o SNP es una variación de un solo nucleótido en una posición genómica específica en una población grande. Es el más prevalente ...

Education

Educación

JoVE Core

Molecular Biology

Biología Molecular

Unit 2

Unidad 2

Analyzing Gene Expression and Function

Análisis de la expresión y función génica

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

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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