Epistasis can be defined as:

Question

Epistasis can be defined as:

Quizplus · Accepted Answer

Epistasis is the interaction between two non-linked genes which causes one gene to mask the expression of the other in the phenotype. 
An example of this is pigmentation in mice. There are two separate genes involved - the gene that dictates the color and the gene that dictates the production of pigment. If a mouse is recessive for the production gene, it cannot produce pigment, no matter what gene it has for the color. Therefore, the gene for pigment production ultimately masks the expression of the gene for color.

Epistasis Can Be Defined As