Factor V Leiden 1691G>A and Prothrombin 20210G>A Genes Polymorphisms, Coagulation Profile and Risk Factors of Deep Vein Thrombosis among Sudanese Patients

Abstract

Background: Deep venous thrombosis (DVT) is one of two manifestations of venous thromboembolism (VTE). VTE is a life threatening disease resulting from multiple interactions between different genetic and environmental factors. Aim: This study aimed to detect the prevalence of factor V Leiden 1691G>A and prothrombin 20210G>A polymorphisms in deep vein thrombosis patients, the coagulation profile and to investigate the role of non-genetic risk factors in the manifestation of DVT. Methods: A total of 192 Sudanese subjects were examined, including 100 DVT patients and 92 healthy controls. Demographic and clinical data were collected using a structured questionnaire. Citrated blood samples of patients and controls were used for coagulation assays PT, APTT, Ddimer Activated protein C resistance and prothrombin fragments1+2. DNAs isolated from EDTA-blood samples were used for the detection of Factor V Leiden 1691G>A and prothrombin 20210G>A polymorphisms using standard and multiplex polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Results: This study included a total of 100 patients (25 males, 75 females) with proven DVT diagnosis and 92 healthy controls (31 males, 61 females). No significant differences in the prevalence of DVT were detected between males and females (p = 0.185). The mean age of the patients was 41.60±17.28 years, while that of controls was 31.65±10.08 years. Ninety-three percent of the DVTs were localized in the left leg and 7% in the right leg. Additionally, 88% of the DVTs were proximal and 12% were distal. Immobility status and cardiovascular disease were the most significantly associated with age (p< 0.001). Among the 75 DVT women enrolled in the study, risk factors that most significantly affected younger female patients were pregnancy and oral contraceptive usage. Significant differences were observed between DVT patients and healthy controls in the levels of prothrombin fragments 1+2(p<0.0001), PT (p<0.0001), APTT (p<0.0001), and D-dimer (p=0.044). Of all subjects, none of the 192 subjects carried the factor V Leiden 1691G>A or prothrombin 20210G>A mutations. Conclusion: No significant differences in the prevalence of DVT between male and female patients in comparison with healthy subjects. D-dimer and prothrombin fragment 1+2 are considered to be useful for the diagnosis of DVT. Previous history of DVT, immobility status and cardiovascular disease were the most significantly associated with age. Women who are pregnant or in postpartum period and those using oral contraceptives are at a higher risk of developing DVT. Factor V Leiden 1691G>A and prothrombin 20210G>A mutations were not associated with DVT in the Sudanese population examined in this study.