Incomplete dominanceand epistasis are both terms that define genetic relationships. What is the most basic distinction between these terms?

Incomplete dominance contrasts the relationship described by John Gregor Mendel by the rule of dominance (when a dominant allele suppresses the effect of recessive allele completely).

In incomplete dominance, the dominant allele cannot completely mask the effect of recessive, and both alleles give mixed effects.

Epistasis is the phenomenon used in genetics that describes the relationship between different genes when the expression of one gene is affected by the presence of another one or more genes.

As described by Mendel, it is also a gene interaction that variates the genetic relationships. It states that all genes assort independently and give their individual effect.

Incomplete dominance involves only different alleles of the same gene means it involves only one gene locus. For example, in Mirabilis jalapa, the dominant allele for the red color of the flower cannot mask the recessive allele of the white color, and offspring with pink colored flower is produced.

Epistasis is the interaction of two or more genes, so it involves two or more gene loci. One example of epistasis is polygenic inheritance in skin color when three genes decide the skin color in humans.