Factor V Leiden increases plasma F1+2 levels both in normal and deep venous thrombosis subjects

Background and Objectives. A simple approach to understanding molecular mechanisms leading to thrombosis is the definition of how genetic factors influence biochemical parameters of coagulation. Conflicting data have been reported regarding the role and the genotype of factor V plays in the control of plasma F1+2 levels. The aim of this study was to test whether the factor V Leiden mutation affects F1+2 levels. Design and Methods. We studied the effect of factor V Leiden mutation (detected by the polymerase chain reaction technique) on plasma F1+2 levels in 418 normal subjects and 39 subjects affected by deep venous thrombosis. Results. In both normal subjects and those with venous thrombosis, heterozygotes for the Leiden mutation showed significantly higher plasma levels of F1+2 (p