Name: using crosses to group mutations
Uploaded: 2021-04-07T12:12:00.000Z
Duration: 49 s
Channel: JoVE

Иногда различные мутации могут привести к одному и тому же фенотипу, например, к потере окраски птичьих перьев. Находятся ли эти мутации в одном гене или в двух разных генах, можно определить с помощью теста на комплементацию.
Рассмотрим разведение между двумя курицами-мутантами. Если один и тот же ген мутирует у обоих родителей, потомство унаследует мутацию и будет казаться белым.
С другой стороны, если потомство выглядит коричневым, как у птицы дикого типа, то это указывает на то, что у родителей были мутации в двух разных генах.
Хотя каждый родительский ген имел мутацию, они работали вместе, чтобы создать фенотип дикого типа. Это явление называется комплементацией.

<ol>
	<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>

Тесты комплементации

Complementation Tests

Тест комплементации — это простое скрещивание, позволяющее определить, расположены ли две мутации в одном и том же гене или в разных генах. Впервые его исполнил Эдвард Льюис в 1940-х годах во время работы над дрозофилами. Он разработал тест для определения местоположения и расположения различных мутаций в хромосомах. Организмы, гетерозиготные по разным мутациям, скрещивают попарно во всех комбинациях. Если мутации присутствуют в разных генах, они могут дополнять друг друга, обеспечивая недостающий генетический элемент, создавая фенотип дикого типа. Однако, если обе мутации принадлежат одному и тому же гену, они не могут дополнять друг друга и не проявляют фенотип дикого типа. Говорят, что мутации, которые не дополняют друг друга, находятся в одной группе комплементации. Мутации, дополняющие друг друга, принадлежат к разным группам комплементации.

Тест на комплементацию — это простое скрещивание, позволяющее определить, находятся ли две мутации в одном гене или в разных генах. Впервые она была исполнена...

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

using crosses to group mutations

A complementation test uses a simple cross to find out whether two mutations are in the same gene or in different genes. It helps show how mutations are arranged on chromosomes. Edward Lewis first performed this test in the 1940s while studying fruit flies.

To do the test, organisms heterozygous for different mutations are crossed pairwise in all combinations. If the mutations are in different genes, they can complement each other. In that case, each mutation provides the missing genetic element, and the offspring shows a wild-type phenotype.

If both mutations are in the same gene, they cannot complement each other. The offspring does not show the wild-type phenotype. Mutations that fail to complement each other are placed in the same complementation group, while mutations that do complement each other belong to different complementation groups.

Using Crosses to Group Mutations

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complementation tests

A complementation test uses a simple cross to find out whether two mutations are in the same gene or in different genes. It helps show how mutations are arranged on chromosomes. Edward Lewis first performed this test in the 1940s while studying fruit flies. To do the test, organisms heterozygous for different mutations are crossed pairwise in all combinations. If the mutations are in different genes, they can complement each other. In that case, each mutation provides the missing genetic...

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key terms and concepts

See how complementation tests use pairwise crosses to tell whether mutations are in the same gene or different genes, and how complementation groups are formed.

Using Crosses to Group Mutations | 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.

Using Crosses to Group Mutations

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