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

A volte, mutazioni diverse possono produrre lo stesso fenotipo, come la perdita di colorazione nelle piume degli uccelli. Se queste mutazioni si trovano nello stesso gene o in due geni diversi, può essere determinato utilizzando un test di complementazione.
Consideriamo l'accoppiamento tra due polli mutanti. Se lo stesso gene è mutato in entrambi i genitori, la prole erediterà la mutazione e apparirà bianca.
D'altra parte, se la prole appare marrone come l'uccello di tipo selvatico, allora ciò indicherebbe che i genitori avevano mutazioni in due geni diversi.
Sebbene ogni gene parentale avesse una mutazione, hanno lavorato insieme per produrre un fenotipo wild-type. Questo fenomeno è chiamato complementazione.

<ol>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf e Richard E. Michod. "Danno genetico, mutazione ed evoluzione del sesso". Science 229, n. 4719 (1985): 1277-1281.</li>
</ol>

test di complementazione

Complementation Tests

Un test di complementazione è un semplice incrocio per identificare se le due mutazioni sono localizzate sullo stesso gene o su geni diversi. Fu eseguito per la prima volta da Edward Lewis negli anni '40 mentre lavorava sui moscerini della frutta. Ha sviluppato il test per identificare la posizione e la disposizione di diverse mutazioni sui cromosomi.

Gli organismi eterozigoti per diverse mutazioni vengono incrociati a coppie in tutte le combinazioni. Se presenti su geni diversi, le mutazioni possono completarsi a vicenda fornendo l'elemento genetico mancante producendo un fenotipo wild-type. Tuttavia, se entrambe le mutazioni appartengono allo stesso gene, non possono completarsi a vicenda e non riescono a mostrare il fenotipo wild-type. Si dice che le mutazioni che non riescono a completarsi a vicenda appartengano allo stesso gruppo di complementazione. Le mutazioni che si completano a vicenda appartengono a diversi gruppi di complementazione.

Test di complementazione

Un test di complementazione è un semplice incrocio per identificare se le due mutazioni si trovano sullo stesso gene o su geni diversi. È stato eseguito per la prima volta da ...

Education

Didattica

JoVE Core

Molecular Biology

Biologia Molecolare

Unit 2

Unità 2

Analyzing Gene Expression and Function

Analisi dell'espressione e della funzione genica

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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

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Le video animazioni di JoVE Core Molecular Biology, organizzate in video lezioni, illustrano i processi molecolari cellulari in maniera chiara e concisa. Inoltre, nei video di "scienziati in azione", i concetti scientifici vengono applicati e dimostrati da ricercatori attraverso esperimenti in laboratorio.

Using Crosses to Group Mutations

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