Question

can someone explain to me about epistasis?

Answer 1

Epistasis occurs when you have two different genes that affect the same trait. These genes may encode enzymes in the same pathway. Let's say Gene A encodes enzyme A which makes a blue pigment in flowers. And Gene B encodes enzyme B which turns the blue pigment into a red pigment. The wild type flower is red, because both genes A and B are functional. If gene B is non-functional (genotype = AAbb, where the recessive b indicates a non-functional allele of gene B), the flowers will be blue. If gene A is nonfunctional, then the flowers will be white because no pigment is made. In that case, both aaBB and aabb genotypes produce white flowers. We say that gene A is epistatic to gene B because the genotype at A can hide the genotype of gene B.

Answer 2

Epistasis - the interaction between two or more genes to control a single phenotype.
Example: The B allele in guinea pigs makes black fur, so any pig with a dominant allele is black. However, the P gene determines the deposition of pigment, so that without a P allele, pigment is not deposited. Not matter how many B alleles ther are, there is no black fur without a P allele. Guinea pigs with the genotype BBpp are, therefore, white, and those that are BBPp are black.

The P gene is epistatic to the B gene.

Answer 3

thanks guys....u rock