Relation between Penetrance and Expressivity
Penetrance is the probability of a gene getting expressed. In some conditions though a dominant allele is present but its phenotype is not visible. For example, the presence of a dominant allele leads to polydactyly in humans but it is not observed in all individuals containing this gene.
Expressivity is the condition in which variable phenotypes are observed in the individuals that contain a penetrant allele. Thus in the individuals that contain a penetrant allele for polydactyly, an extra digit may be observed in one or more appendages. The digit may be full sized or short.
Expressivity
Expressivity is a basic concept that explains the intricate relationship between an individual’s genetics and their observable characteristics. It describes the degree of variability with which the corresponding characteristics of a gene are expressed. It acts as a pivot for understanding the in-depth knowledge of genetic disorders and hereditary characteristics.
Expressivity acts as a crucial lens to study and comprehend the manifestation of genetic traits. In this article, we will read about what expressivity is, why expressivity occurs, types of expressivity, factors affecting expressivity, the relation between penetrance and expressivity, and the clinical implications of expressivity.
Table of Content
- What is Expressivity?
- Why does Expressivity occur?
- Types of Expressivity
- Factors Affecting Expressivity
- Relation between Penetrance and Expressivity
- Clinical Implications of Expressivity