Expressiveness

This article covers the genetic term. For the linguistic term see expressivity (linguistics)

In genetics, expressivity (degree of expression) refers to the different degrees of expression of a phenotypic trait with an identical genotype . If this expression is different despite the identical genotype, one speaks of a variable expressivity. A variable expressivity can be caused, for example, by environmental influences during and after embryonic development.

Variable expressivity describes continuous characteristics. It must be distinguished from penetrance , which categorically describes the actual frequency of a trait in a given genotype .