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

Czasami różne mutacje mogą powodować ten sam fenotyp, na przykład utratę zabarwienia ptasich piór. To, czy mutacje te występują w tym samym genie, czy w dwóch różnych genach, można określić za pomocą testu komplementacji.
Weźmy pod uwagę hodowlę między dwoma zmutowanymi kurczakami. Jeśli ten sam gen zostanie zmutowany u obojga rodziców, potomstwo odziedziczy mutację i będzie wyglądało na białe.
Z drugiej strony, jeśli potomstwo wydaje się brązowe jak ptak typu dzikiego, oznaczałoby to, że rodzice mieli mutacje w dwóch różnych genach.
Chociaż każdy gen rodzicielski miał mutację, współpracowały one ze sobą, aby wytworzyć fenotyp typu dzikiego. Zjawisko to nazywa się komplementacją.

<ol>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf i Richard E. Michod. "Uszkodzenia genetyczne, mutacje i ewolucja płci". Science 229, nr 4719 (1985): 1277-1281.</li>
</ol>

test komplementacji

Complementation Tests

Test komplementacji to proste krzyżowanie mające na celu określenie, czy dwie mutacje znajdują się w tym samym genie, czy w różnych genach. Po raz pierwszy został wykonany przez Edwarda Lewisa w latach czterdziestych XX wieku podczas pracy nad muszkami owocowymi. Opracował test umożliwiający identyfikację lokalizacji i rozmieszczenia różnych mutacji na chromosomach. Organizmy heterozygotyczne pod względem różnych mutacji krzyżuje się parami we wszystkich kombinacjach. Jeśli mutacje występują w różnych genach, mogą się wzajemnie uzupełniać, dostarczając brakujący element genetyczny tworzący fenotyp typu dzikiego. Jeśli jednak obie mutacje należą do tego samego genu, nie mogą się wzajemnie uzupełniać i nie wykazują fenotypu typu dzikiego. Mówi się, że mutacje, które nie uzupełniają się, należą do tej samej grupy komplementacyjnej. Mutacje, które się uzupełniają, należą do różnych grup komplementacji.

Test komplementacji

Test komplementacji to proste krzyżowanie w celu określenia, czy dwie mutacje są zlokalizowane na tym samym genie, czy na różnych genach. Po raz pierwszy został wykonany przez ...

Education

JoVE Core

Molecular Biology

Biologia molekularna

Unit 2

Jednostka 2

Analyzing Gene Expression and Function

Analiza ekspresji i funkcji genów

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

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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