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

Às vezes, mutações diferentes podem produzir o mesmo fenótipo, como perda de coloração nas penas das aves. Se essas mutações estão no mesmo gene ou em dois genes diferentes, pode ser determinado usando um teste de complementação.
Considere a criação entre duas galinhas mutantes. Se o mesmo gene sofrer mutação em ambos os pais, a prole herdará a mutação e parecerá branca.
Por outro lado, se a prole parecer marrom como o pássaro do tipo selvagem, isso indicaria que os pais tinham mutações em dois genes diferentes.
Embora cada gene parental tivesse uma mutação, eles trabalharam juntos para produzir um fenótipo de tipo selvagem. Esse fenômeno é chamado de complementação.

<ol>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf e Richard E. Michod. "Dano genético, mutação e evolução do sexo." Ciência 229, nº 4719 (1985): 1277-1281.</li>
</ol>

testes de complementação

Complementation Tests

Um teste de complementação é um cruzamento simples para identificar se as duas mutações estão localizadas no mesmo gene ou em genes diferentes. Foi executada pela primeira vez por Edward Lewis na década de 1940 enquanto trabalhava com moscas-das-frutas. Ele desenvolveu o teste para identificar a localização e a disposição de diferentes mutações nos cromossomos. Organismos heterozigotos para diferentes mutações são cruzados aos pares em todas as combinações. Se presentes em genes diferentes, as mutações podem complementar-se, fornecendo o elemento genético em falta, produzindo um fenótipo de tipo selvagem. No entanto, se ambas as mutações pertencem ao mesmo gene, não podem complementar-se e não exibem o fenótipo do tipo selvagem. Diz-se que as mutações que não se complementam estão no mesmo grupo de complementação. As mutações que se complementam pertencem a diferentes grupos de complementação.

Testes de Complementação

Um teste de complementação é um cruzamento simples para identificar se as duas mutações estão localizadas no mesmo gene ou em genes diferentes. Foi realizado pela primeira vez por ...

Education

JoVE Core

Molecular Biology

Biologia Molecular

Unit 2

Unidade 2

Analyzing Gene Expression and Function

Analisando a Expressão e a Função Gênica

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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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genetic screens

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test cross

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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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experimental rnai

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Reporter genes are protein-coding genes used to track gene activity in cells. They are often tagged to a gene of interest so scientists can see whether that gene is present or active. When the tagged genes are expressed together, reporter genes can produce visible signals such as fluorescence or luminescence. These signals help show the presence or absence of a gene of interest in an organism. They can also reveal the pattern of gene expression or the location of a DNA segment or protein...

in-situ hybridization

ISH Probes for DNA and RNA Detection

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transgenic plants

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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 Biologia Molecular mostra os processos moleculares da célula através de vídeos de animação claros e concisos. Além disso, nos vídeos de Cientistas em ação, a aplicação desses conceitos é demonstrada por meio de experimentos reais em laboratórios modernos.

Using Crosses to Group Mutations

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