The association between common C677T mutation in methylenetetrahydrofolate reductase gene and the risk of venous thrombosis in an Iranian population

Background: Venous thrombosis is a multicausal disease involving acquired and genetic factors. The prevalence of methylenetetrahydrofolate reductase (MTHFR) C677T genotypes and its association with venous thrombosis is not established in the Iranian population. In this study we investigated a possible association between fasting hyperhomocysteinemia and C677T mutation in the MTHFR gene with venous thrombosis. Materials and Methods: We studied 200 venous thrombotic patients and 100 healthy controls, of similar age and sex. Mutation analysis was carried out by PCR-RFLP, and the homocysteine level was measured by EIA. Results: No significant differences in the frequency of C677T genotypes were observed between patients and controls (P=0.2). The frequency of the T allele was 21 and 27.2 in controls and patients, respectively (odds ratio, 1.27; 95 CI, 0.83-1.94, P=0.15). Fasting homocysteine level was significantly higher in patients than controls (P=0.001). Conclusions: We concluded that hyperhomocysteinemia, but not MTHFR C677T mutation, is a significant risk factor for venous thrombosis in the Iranian population, and measuring the level of homocysteine is less expensive and more useful than the genetic test for the MTHFR mutation.