Activated protein C resistance (APC-R) because of clotting factor V Leiden mutation (FVL; Arg506Gln; G1691A) is a risk factor for the development of venous thromboembolic disorders (VTE).
Its allelic frequencies were found to differ significantly (P=0.003) between subjects selected for increased APCR in the absence of the FV R506Q mutation (n=70, normalized ratios </=0.80), and for increased APC sensitivity (n=98, normalized ratios >/=1.31).
To ascertain whether relationship exists between the presence of APC resistance [a hypercoagulable state due to a mutation (R506Q) in the factor V gene] and the occurrence of pre-eclampsia (PE), intrauterine growth retardation (IUGR), and pregnancy bleeding complications.
Factor VThr306 is the first description of a mutation affecting the Arg306 APC cleavage site and is the only mutation, other than factor V Leiden (Arg506-->Gln), that has been found in association with APC resistance.
Resistance to activated protein C (APCR), in the majority of cases due to arginine506 (Arg506) to glutamine (Gln) mutation in the factor V gene, has emerged as the most important hereditary cause of venous thrombo-embolism.
Seventy women with thrombosis in pregnancy were investigated for the presence of APC resistance and the associated Arg506-Gln mutation in coagulation factor V. The mutation was found in 46% of the investigated women.
Resistance to activated protein C (APC resistance) due to the factor V mutation 506 Arg-->Gln (factor V Leiden) is the most prevalent inherited risk factor for venous thromboembolism.