Prevalence of Arg306 mutation of the factor V gene in Korean patients with thrombosis.

Accessible online at: http://BioMedNet.com/karger Dear Sir, Factor V Leiden is the most common inherited risk factor that has yet been identified for thromboembolism [1, 2]. However, this mutation has been reported to be rare in several ethnic populations including Koreans [3–5]. Recently, Chan et al. [6] analyzed 83 unrelated Hong Kong Chinese for the presence of genetic variants of factor V gene (exon 7, 10 and 13, where the codons for Arg306, Arg506, and Arg 679 are located, respectively) and the mutation in exon 10 or exon 13 was not detectable in any of the 83 subjects. However, they have identified a novel mutation (A1090G) in exon 7 that resulted in Arg306→Gly substitution in 2 thrombotic patients and 1 nonthrombotic subject. In addition, Williamson et al. [7] found Arg306→Thr mutation in 1 patient from a carefully selected group of 17 patients with venous thrombosis and confirmed activated protein C resistance in the absence of the common Gln506 mutation. Therefore, we investigated the prevalence of Arg306 mutation of factor V in Korean patients with thrombosis. The study group (49 males and 62 females) included 111 unrelated individuals (median age 57 years, range 20–86 years) who had been referred due to venous or arterial thrombotic events (21 deep vein thrombosis, 7 pulmonary embolism, 4 isolated mesenteric or portal veins, 60 stroke, 8 myocardial infarct, 11 peripheral artery obstructive diseases). Sequence variations were detected by polymerase chain reaction and restriction enzyme analysis according to Williamson et al. [7]. As a result, a normal digest pattern was detected in all 111 patients. This finding demonstrates a very low prevalence of Arg306 mutation of the factor V gene in the Korean population and this mutation may not play a major role in the pathogenesis of venous or arterial thrombosis.