What is the penetrance of Factor V Leiden?

The penetrance of Factor V Leiden is characterized as incomplete penetrance. This means that not every individual who carries the mutation will develop the associated condition or phenotype. In the case of Factor V Leiden, individuals with this specific genetic mutation may have an increased risk for venous thromboembolism, but not all carriers will experience these thrombotic events. Various factors influence this, including environmental conditions, lifestyle choices, and the presence of other genetic predispositions, which contribute to the variability in expressing the phenotype associated with the mutation.

Understanding incomplete penetrance is crucial for molecular biology professionals, as it underscores the complexity of genetic contributions to diseases and health outcomes, indicating that mutations can predispose individuals to a condition without guaranteeing its manifestation in every case.