The present study was undertaken to  investigate the relationship between eNOS polymorphism and acute ischemic stroke in the Indian population.

 Endothelial nitric oxide synthase (eNOS) is an enzymatic marker whose genetic polymorphism might predispose to acute ischemic stroke via its effects on vascular endothelial function, and its role in atherosclerosis due to blood stasis thus making it a plausible genetic risk factor for stroke. The limited number of studies have failed to prove a conclusive relationship between eNOS genetic polymorphism and acute ischemic stroke which still remains controversial.

  We performed a case control study recruiting 307 subjects including 153 cases of acute ischemic stroke and 154 age and sex matched healthy controls. The eNOS (Glu298Asp) polymorphism was identified by the PCR amplification of the target region followed by restriction enzyme digestion and genotyping on 3% Agarose gel. Three genotypes GG, GT and TT were obtained. Statistical analysis was done using Microsoft excel spreadsheets and SPSS software (version 20).

A significant association was found between the presence of TT genotype and the risk of acute ischemic stroke (Odds ratio 2.43 pvalue=0.038) in our study. We did not find a significant association between the presence of TT genotype and the traditional cardiovascular risk factors for stroke. However the TT genotype was significantly associated with the presence of altered consciousness at presentation among stroke cases (Odds Ratio 5.27, 95% CI 1.59-17.04 ,p value=0.003) as well as with the occurrence of seizures at presentation (Odds Ratio 7.98 ,95% CI 1.99 -32.09 p value=0.007).  

Our study found a significant association between the presence of Endothelial nitric oxide synthase (eNOS)polymorphism (Glu298Asp) and the risk of developing acute ischemic stroke  and there was a significant association between the presence TT genotype and altered level of consciousness and seizures at presentation among stroke cases.