Impact of inherited thrombophilic factors on deep vein thrombosis in individuals in south Iran

Inherited thrombophilic factors are risk factors for venous thrombosis. This study aimed to estimate the frequencies of factor V Leiden (FVL) and prothrombin G20210A mutations and protein C, protein S, and antithrombin III deficiencies in individuals from south Iran and the impact of these factors on the incidence of venous thrombosis in this area. The study population included 135 patients with venous thrombosis and 1200 healthy blood donors. The protein C, protein S, and antithrombin III activities were measured, and the prothrombin 20210A and FVL mutations were analyzed using polymerase chain reaction-based highresolution melting analysis and restriction fragment length polymorphism with genomic DNA. The frequencies of protein C, protein S, and antithrombin deficiencies in the control group were 0.33% (95% confidence interval [CI]=0.30Π 0.36), 0.25% (95% CI=0.23Π0. 27), and 0.08% (95% CI=0.06Π0. 10), respectively, and for the patient group were 5.3% (95% CI=1.5Π9. 1), 3.8% (95% CI=0.5Π7. 0), and 4.5% (95% CI=0.9Π8. 0), respectively. The allele frequencies of FV Leiden and prothrombin 20210A in the control group were (0.0175 [CI=0.0122Π0. 0227] and 0.0200 [CI=0.0144Π0. 0256], their frequencies in the patients were significantly high 0.196 and 0.181, respectively. Thus, in the area studied, the genetic background clearly affected the onset age and the clinical course of thrombosis. Approximately 41.5% of the patients who were from the study area and had DVT had at least 1 of these predisposing genetic factors.