Two common genetic thrombotic risk factors: Factor V Leiden and prothrombin G20210A in adult Turkish patients with thrombosis

The prevalence of genetic risk factors for thrombosis varies greatly in dif ferent parts of the world, both in patients with thrombosis and in the gene ral population. Factor V Leiden (FVL) and prothrombin G20210A (PT G20210A) mutations are the most common genetic defects leading to thrombosis. We hav e previously reported that those two thrombotic risk alleles are frequently found in Turkish children with thrombosis, The aim of the present study wa s to investigate the frequency of FVL and PT G20210A and their clinical man ifestations in adult Turkish patients with thrombosis. Between January 1997 end February 2000, 146 patients with documented thrombosis were investigat ed in our center for the presence of the FVL and PT G20210A mutations. Fort y-five of 146 patients with thrombosis (30.8%) were detected to have FVL mu tation. Among those cases with the FVL mutation, seven (4.8%) had homozygot e and 38 (26%) had heterozygote mutation. The PT G20210A mutation was detec ted in 10 of the 146 patients with thrombosis (6.8%). Another six cases (4. 1%) had both FVL and PT G20210A mutations. The overall frequency of these t wo common risk alleles in our adult population with thrombosis was 41.6%. O ur findings reveal that FVL and PT G20210A mutations are significant geneti c risk factors contributing to the pathophysiology of thrombosis in the Tur kish population. Am. J. Hematol. 67:107-111, 2001, (C) 2001 Wiley-Liss, Inc .