factor V Leiden

noun
factor V Lei·​den | \ -ˈlī-dᵊn How to pronounce factor V Leiden (audio) \

Medical Definition of factor V Leiden

1 : a point mutation producing an abnormal version of factor V that is resistant to inactivation and causes prolonged clotting of blood
2 also factor V Leiden thrombophilia : a genetic disorder caused by factor V Leiden that is marked by an increased risk of abnormal blood clot formation leading especially to deep vein thrombosis or pulmonary embolism

Note: Factor V Leiden is inherited as an autosomal dominant trait requiring that only one parent pass on a copy of the defective gene on a chromosome other than a sex chromosome. When both parents carry the defective gene, factor V Leiden is inherited as a recessive, more serious condition.