Prevalence of the G1691A mutation in the factor V gene (factor V Leiden) and the G20210A prothrombin gene mutation in the Thai population

Abstract

We investigated the prevalence of a genetic variation in the factor V gene (G1691A Leiden mutation) and the prothrombin gene (G20210A) using polymerase chain reaction techniques in samples from 500 normal Thai population and among 50 unselected Thai patients with an objectively confirmed history of deep venous thrombosis. The prevalence of factor V Leiden and the prothrombin G20210A gene mutation in a group of 500 healthy controls was 0.2% in both groups (allele frequency of 0.1%). Of the 50 adult patients studied, none was a carrier of factor V Leiden or the prothrombin G20210A gene mutation. Our findings confirm that the prevalence of factor V Leiden and prothrombin G20210A gene mutation is lower among Asians than Caucasians and that the distribution of factor V Leiden is similar to that of the prothrombin G20210A variant. The low prevalence of these two mutations can, at least in part, account for the lower frequency of deep venous thrombosis reported in the Thai population. Screening for factor V Leiden and prothrombin gene mutation is of limited benefit and may not be cost-effective in Thai patients with the first episode of deep venous thrombosis.

Incidence and cumulative recurrence rates of venous thromboembolism in the Taiwanese population

“…The cause of the lower incidence of VTE in the Taiwanese population remains unclear, but may be partly attributed to a lower incidence of primary hypercoagulable disease predisposing to VTE. Previous studies have shown a lower incidence of FV Leiden mutation in Asian populations (0.5%) than in Caucasians (5%) [20][21][22]. In addition, Steffen et al [23] reported that a diet including abundant vegetables, fish and little meat was associated with lower risk of incident VTE.…”

Low prevalence of Factor V Leiden and the prothrombin G20210A mutation in a healthy population from the central-south region of Chile

“…20,21 The Australian population includes many ethnic groups among them the Asian population, Caucasian and Middle East, are those who had shown a frequency of 0.3%, 2.8% and 6.2%, respectively. 22 On the other hand, Asian population presented a lower prevalence of this polymorphism than Thai people with 0.5% 22 and Japanese, Chinese, Korean and Mongolian whose prevalence is closed to 0%. 3 It is interesting to observe that the prevalence of FV Leiden between the healthy population of a region in Turkey is 8.7% of which 1% presents homozygosity 24 and a Lebanese community showed a frequency of 13.8%.…”

The Epidemiology of Venous Thromboembolism

“…16 The relatively low incidence of VTE in Asians and Hispanics has not been explained, but may relate to a lower prevalence of genetic factors predisposing to VTE, such as factor V Leiden in Asian populations (0.5%) compared with Caucasians (5%). [17][18][19] In venographic studies of patients recovering from hip replacement surgery, the incidence of asymptomatic VTE in Asians appears comparable with that in North America, 20 -22 suggesting that the difference in VTE incidence may be related to less efficient inactivation of coagulation by activated protein C or less fibrinolytic activity among Caucasians. The lower incidence of VTE in Hispanics than in African Americans cannot be explained by a lower prevalence of factor V Leiden, as this genetic condition is present in Ϸ2% of Hispanic and Ͻ1% of African Americans.…”