Home > Encyclopedia of Genetic Disorders > Factor V Leiden thrombophilia

Definition

Factor V Leiden thrombophilia is a common genetic disorder that leads to a predisposition or increased chance to develop blood clots in the veins (venous thrombosis).

Description

Factor V Leiden thrombophilia is a disorder caused by an inherited change or mutation in the genetic instructions for making a substance called factor V. The factor V change leads to an increased chance to develop blood clots in blood vessels.

Blood clots form in two steps. In the first step, the body produces platelets that are "sticky" and can form initial plugs or clots when needed. However, the first platelets only form the first temporary plugs. To form a more lasting plug or clot the platelets release chemicals to attract more platelets and other substances called clotting factors (or...