Relationship between Factor V Leiden Gene Variant and Risk of Ischemic Stroke: A Case-Control Study

Background: Factor V Leiden is the most common genetic variation among the blood coagulation pathway which leads to prothrombotic state, therefore, is considered an important gene for understating the stroke mechanism. Aim: The aim of the present study is to determine the relationship between single nucleotide polymorphism at G1691A position of Factor V gene and risk of ischemic stroke (IS) in North Indian population. Materials and Methods: In a retrospective case-control study, 250 patients with IS and 250 age-and gender-matched controls were enrolled in the period of October 2012 to September 2014 from in-and out-patient department of Neurology, All India Institute of Medical Sciences, New Delhi, India. Deoxyribonucleic acid for each case and control was isolated from peripheral blood using phenol-chloroform extraction method. Polymerase chain reaction-restriction fragment length polymorphism method was used to determine the polymorphism. Data were analyzed using STATA Software Version 13. Results: The mean age of IS patient was 52.8 +/- 12.5 years and in control group was 50.97 +/- 12.7 years. Genotypic frequency distributions were in accordance with Hardy-Weinberg equilibrium in both cases and controls. As expected hypertension, diabetes, dyslipidemia, smoking, heavy alcohol intake, family history of stroke, and poor economic status were significantly associated with the risk of IS. Multivariate analysis revealed 5.17 times higher odds for developing the risk of large vessel subtype of IS in patients carrying Factor V Leiden G1691A gene variation as compared to control subjects (OR, 5.17; 95% CI, 1.32-20.3, P = 0.01). Conclusion: The present study suggests that Factor V Leiden G1691A polymorphism may be significantly associated with the risk of large vessel subtype of IS. Large sample size studies using prospective cohort designs are required to corroborate the present findings.