Question

What is an example of linked genes ?

Answer 1

Linkage:

1. The physical association of genes on the same chromosome is called linkage.
2. The strength of linkage depends upon the distance between two genes.
3. When two genes or more genes are linked together on the same chromosome the tendency to form recombinants is reduced.

Linked genes :

1. The two or more genes are said to be linked when they are located on the same chromosome and cannot segregate independently as they are inherited together.
2. The linked genes are arranged linearly.

Example of linked genes is Drosophila:

1. The cross between wild type Drosophila with grey body long-wings ( BBVV) and mutant variety of Drosophila (bbvv) black body with vestigial wings was performed.
2. This resulted in F1 generation with genotype (BbVv), with a similar phenotype to the wild type parent i.e. grey body long-wings.
3. Again the hybrid male of the F1 generation was backcrossed with a recessive female with a phenotype black body with vestigial wings.
4. This resulted in parental combinations, indicates that grey body character is inherited together with long wings ( the genes of both body color and wings are linked together).
5. This shows complete linkage as no nonparental combinations appeared in the F2 generation.