Congenital and acquired activated protein C resistance.
Resistance to the anticoagulant action of activated protein C, APC resistance, is a highly prevalent risk factor for venous thrombosis among individuals of Caucasian origin. In most cases, APC resistance is associated with a single missense mutation in the gene for coagulation factor V (FVLeiden), which predicts the replacement of Arg506 with a Gln at one of the cleavage sites for APC in factor V.
