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

Manchmal können verschiedene Mutationen den gleichen Phänotyp hervorrufen, wie z. B. der Verlust der Färbung von Vogelfedern. Ob diese Mutationen im selben Gen oder in zwei verschiedenen Genen vorliegen, kann mit einem Komplementationstest festgestellt werden.
Denken Sie an die Zucht zwischen zwei mutierten Hühnern. Ist bei beiden Elternteilen das gleiche Gen mutiert, erbt der Nachwuchs die Mutation und erscheint weiß.
Erscheint der Nachwuchs hingegen braun wie der Wildtyp-Vogel, dann deutet dies darauf hin, dass die Eltern Mutationen in zwei verschiedenen Genen hatten.
Obwohl jedes Elterngen eine Mutation aufwies, arbeiteten sie zusammen, um einen Wildtyp-Phänotyp zu erzeugen. Dieses Phänomen wird als Komplementation bezeichnet.

<ol>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf und Richard E. Michod. "Genetische Schäden, Mutationen und die Evolution des Geschlechts." Science 229, Nr. 4719 (1985): 1277-1281.</li>
</ol>

komplementierungstests

Complementation Tests

Ein Komplementierungstest ist eine einfache Kreuzung, um zu identifizieren, ob zwei Mutationen auf demselben Gen oder auf verschiedenen Genen liegen. Dieser Test wurde erstmals in den 1940er Jahren von Edward Lewis durchgeführt, während er an Fruchtfliegen arbeitete. Er entwickelte den Test, um die Lage und Anordnung verschiedener Mutationen auf den Chromosomen zu bestimmen.

Organismen, die für verschiedene Mutationen heterozygot sind, werden paarweise in allen Kombinationen gekreuzt. Liegen die Mutationen auf verschiedenen Genen, können sie sich gegenseitig ergänzen, indem sie das fehlende genetische Element bereitstellen, was zu einem Wildtyp-Phänotyp führt. Gehören jedoch beide Mutationen zum selben Gen, können sie sich nicht ergänzen und zeigen keinen Wildtyp-Phänotyp. Die Mutationen, die sich nicht ergänzen, werden als in derselben Komplementierungsgruppe befindlich angesehen. Die Mutationen, die sich gegenseitig ergänzen, gehören zu unterschiedlichen Komplementierungsgruppen.

Komplementierungstests

Ein Komplementationstest ist eine einfache Kreuzung, um festzustellen, ob die beiden Mutationen auf demselben Gen oder auf unterschiedlichen Genen lokalisiert sind. Es wurde uraufgeführt von ...

Education

Lehre

JoVE Core

Molecular Biology

Molekularbiologie

Unit 2

Einheit 2

Analyzing Gene Expression and Function

Analyse von Genexpression und -funktion

KEY TERMS AND CONCEPTS

KERNBEGRIFFE UND KONZEPTE

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

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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

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Using Crosses to Group Mutations

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