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

Sometimes, different mutations can produce the same phenotype, such as loss of coloration in bird feathers. Whether these mutations are in the same gene or in two different genes, can be determined using a complementation test.
Consider the breeding between two mutant chickens. If the same gene is mutated in both parents, the offspring will inherit the mutation and appear white.
On the other hand, if the offspring appears brown like the wild-type bird, then this would indicate that the parents had mutations in two different genes.
Although each parental gene had a mutation, they worked together to produce a wild-type phenotype. This phenomenon is called complementation.

complementatietesten

Complementation Tests

Een complementatietest is een eenvoudige kruising om te identificeren of de twee mutaties zich op hetzelfde gen of op verschillende genen bevinden. Het werd voor het eerst uitgevoerd door Edward Lewis in de jaren veertig, terwijl hij aan fruitvliegen werkte. Hij ontwikkelde de test om de locatie en rangschikking van verschillende mutaties op chromosomen te identificeren.

Organismen die heterozygoot zijn voor verschillende mutaties worden in alle combinaties paarsgewijs gekruist. Als de mutaties op verschillende genen aanwezig zijn, kunnen ze elkaar aanvullen door het ontbrekende genetische element aan te leveren, waardoor een wildtype fenotype ontstaat. Als beide mutaties echter tot hetzelfde gen behoren, kunnen ze elkaar niet aanvullen en falen ze in het vertonen van het wildtype fenotype. Van de mutaties die elkaar niet aanvullen, wordt gezegd dat ze zich in dezelfde complementatiegroep bevinden. De mutaties die elkaar aanvullen behoren tot verschillende complementatiegroepen.

Complementatietesten

A complementation test is a simple cross to identify whether the two mutations are located on the same gene or different genes. It was first performed by ...

Education

JoVE Core

Molecular Biology

Moleculaire biologie

Unit 2

Onderdeel 2

Analyzing Gene Expression and Function

Analyse van genexpressie en functie

KEY TERMS AND CONCEPTS

BELANGRIJKE TERMEN EN CONCEPTEN

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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