Name: gene interaction maps in epistasis
Uploaded: 2023-04-30T10:14:33.000Z
Duration: 1 min 9 s
Channel: JoVE

Противоположной связью между двумя генами является эпистаз, когда один ген маскирует или изменяет экспрессию другого. Говорят, что влияющий ген эпистатичен по отношению к маскируемому гену.
Например, ген, кодирующий связанный с тирозиназой белок 1, или TYRP1, определяет цвет шерсти собак — черный или коричневый.
Другой ген, Tyr, кодирует фермент тирозиназу, который отвечает за пигментацию у животных. Мутация в этом гене может привести к отсутствию пигмента, в результате чего у собаки-альбиноса отсутствует окраска.
Порядок, в котором экспрессируются эти два гена, может быть определен с помощью теста на эпистаз.
Если мутация в гене Tyr приводит к появлению собаки-альбиноса, которая все еще имеет ген дикого типа TYRP1, можно сделать вывод, что ген Tyr маскирует действие гена TYRP1. Это означает, что Tyr эпистатичен по отношению к TYRP1.

<ol>
	<li>Михельс, К.А. (2002). Анализ эпистаза. В книге «Генетические методы биологических исследований», К.А. Михельс (ред.). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Бернштейн, Харрис, Генри К. Байерли, Фредерик А. Хопф и Ричард Э. Мишо. "Генетические повреждения, мутации и эволюция пола." Наука 229, No4719 (1985): 1277-1281.</li>
</ol>

Эпистазный анализ

Epistasis Analysis

Хотя Мендель выбрал семь неродственных признаков у гороха для изучения сегрегации генов, большинство признаков связаны с множественными взаимодействиями генов, которые создают спектр фенотипов. Когда взаимодействие различных генов или аллелей в разных местах влияет на фенотип, это называется эпистазом. Эпистаз часто предполагает маскировку одного гена или вмешательство в экспрессию другого (антагонистический эпистаз). Эпистаз часто возникает, когда разные гены являются частью одного и того же биохимического пути. Экспрессия гена может зависеть от генного продукта того же биохимического пути. Эпистатический анализ Изучение эпистатических взаимодействий позволяет исследователям определить функциональные взаимоотношения между генами, порядок расположения генов в пути и то, как различные аллели количественно влияют на фенотипы. Рассмотрим биохимическую реакцию, катализируемую множеством белков, кодируемых разными генами. Гены, участвующие в таких биохимических реакциях, могут маскировать или ингибировать другие гены, участвующие в том же биохимическом пути — явление, называемое эпистазом. О таких генах говорят, что они принадлежат к одной эпистазной группе. Анализируя эпистатические отношения между различными генами, ученые могут построить карту порядка функций, которая показывает последовательность событий и генов, участвующих в пути. Этот процесс называется эпистатическим анализом. Аллели, выбранные для эпистатического анализа, должны иметь различные фенотипы. Таким образом, с момента появления концепции эпистаза становится все более очевидным, что большинство биологических систем включают в себя множество генетических элементов, которые взаимодействуют друг с другом множеством и сложным образом.

Хотя Мендель выбрал семь неродственных признаков у гороха для изучения сегрегации генов, большинство признаков включают в себя множественные взаимодействия генов, которые создают спектр ...

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

gene interaction maps in epistasis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene.

Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in the same pathway are considered part of one epistasis group.

Epistatic analysis uses these interactions to reveal how genes are related. Scientists can use it to identify the functional relationship between genes, determine the order of genes in a pathway, and see how different alleles affect phenotypes in a quantitative way. When multiple proteins encoded by different genes take part in a biochemical reaction, epistatic analysis can help build an order-of-function map that shows the sequence of events and the genes involved.

To compare genes in this way, the alleles chosen for analysis must have distinct phenotypes. Since epistasis was first described, it has become clear that many biological systems include genetic elements that interact in complex ways. These interactions help explain why many traits do not follow simple single-gene patterns.

Gene Interaction Maps in Epistasis

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transgenic plants

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epistasis analysis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene. Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in...

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 how epistasis reveals gene interactions, pathway order, and phenotype changes through epistatic analysis in high school biology.

Gene Interaction Maps in Epistasis | JoVE K12

molecular biology

JoVE Core Molecular Biology showcases the molecular processes of the cell through clear and concise animated video lessons. Additionally, in scientist-in-action videos, these concepts' application is demonstrated through real experiments in modern laboratories.

Gene Interaction Maps in Epistasis

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