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

A veces, diferentes mutaciones pueden producir el mismo fenotipo, como la pérdida de coloración en las plumas de las aves. Si estas mutaciones están en el mismo gen o en dos genes diferentes, se puede determinar mediante una prueba de complementación.
Considere la cría entre dos pollos mutantes. Si el mismo gen está mutado en ambos padres, la descendencia heredará la mutación y aparecerá blanca.
Por otro lado, si la descendencia parece marrón como el ave de tipo salvaje, entonces esto indicaría que los padres tenían mutaciones en dos genes diferentes.
Aunque cada gen parental tenía una mutación, trabajaron juntos para producir un fenotipo de tipo salvaje. A este fenómeno se le llama complementación.

<ol>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf y Richard E. Michod. "Daño genético, mutación y la evolución del sexo". Ciencia 229, no. 4719 (1985): 1277-1281.</li>
</ol>

pruebas de complementación

Complementation Tests

Una prueba de complementación es un cruce simple para identificar si las dos mutaciones están ubicadas en el mismo gen o en genes diferentes. Fue interpretado por primera vez por Edward Lewis en la década de 1940 mientras trabajaba con moscas de la fruta. Desarrolló la prueba para identificar la ubicación y disposición de diferentes mutaciones en los cromosomas.

Los organismos heterocigotos para diferentes mutaciones se cruzan por pares en todas las combinaciones. Si están presentes en genes diferentes, las mutaciones pueden complementarse entre sí proporcionando el elemento genético faltante que produce un fenotipo de tipo salvaje. Sin embargo, si ambas mutaciones pertenecen al mismo gen, no pueden complementarse y no exhiben el fenotipo de tipo salvaje. Se dice que las mutaciones que no logran complementarse entre sí están en el mismo grupo de complementación. Las mutaciones que se complementan pertenecen a diferentes grupos de complementación.

Pruebas de complementación

Una prueba de complementación es un cruce simple para identificar si las dos mutaciones se encuentran en el mismo gen o en genes diferentes. Fue interpretado por primera vez por ...

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

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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experimental rnai

RNAi for Gene Silencing and Discovery

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in-situ hybridization

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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 Biología Molecular presenta los procesos moleculares de la célula a través de lecciones claras y concisas de animaciones audiovisuales. Además, en los vídeos de científicos en acción, se muestran aplicaciones de estos conceptos mediante experimentos reales en laboratorios especializados.

Using Crosses to Group Mutations

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