PATHOLOGY

Detailed explanation-1: -Epistasis is the non-allelic gene interaction where the presence of one gene masks the expression of another gene; dihybrid ratio for dominant epistasis becomes 12:3:1.

Detailed explanation-2: -A gene that masks the phenotypic effect of another gene is called an epistatic gene; the gene it subordinates is the hypostatic gene.

Detailed explanation-3: -Epistasis occurs when two (or more) different genes interact to control one single phenotype or trait. The genes must be at different loci, or locations, in the genome. Typically, one gene (the epistatic gene) modifies, suppresses, or enables the expression of a different gene (the hypostatic gene).

Detailed explanation-4: -Definition. Epistasis is a circumstance where the expression of one gene is modified (e.g., masked, inhibited or suppressed) by the expression of one or more other genes.

Detailed explanation-5: -Epistasis can occur when a recessive genotype masks the actions of another gene, or when a dominant allele masks the effects of another gene. Epistasis can be reciprocal: either gene, when present in the dominant (or recessive) form, expresses the same phenotype.