Association of Endothelial Nitric Oxide Synthase Gene Polymor-phisms with Early-Onset Ischemic Stroke in South Indians

Abstract

Aim: The aim of this study was to investigate the association of T-786C, G894T and 4a/b polymor-phisms in the endothelial nitric oxide synthase (eNOS) gene with early-onset ischemic stroke in South Indians.
Methods: We enrolled 177 patients diagnosed with ischemic stroke aged between 15 to 45 years and 219 age- and gender-matched healthy controls. Genotypes of eNOS T-786C, G894T and 4a/b were identified by polymerase chain reaction and restriction fragment length polymorphism.
Results: The allele and genotype frequencies of eNOS 4a/b, T-786C and G894T did not differ sig-nificantly in the patient group compared to controls. Logistic regression analysis indicated the 4a allele to be an independent predictor of ischemic stroke in females (dominant model: OR, 2.46; 95% CI, 1.11 to 5.43; p,/i>=0.026). Marked differences were found in the prevalence of the minor alleles of the three variants when comparing the South Indian population with the reported frequencies from Caucasians. There was also a contrast in the frequencies of 4ab and T-786C variants from other Asians. The genotypes of all three variants were found to be in Hardy-Weinberg equilibrium. There was a lack of significant linkage disequilibria among the variants, and none of the estimated haplo-types increased or decreased the risk of ischemic stroke.
Conclusion: The eNOS intron 4a/b polymorphism can predict early-onset ischemic stroke in south Indian women.