Genetic analysis of eNOS gene polymorphisms in association with recurrent miscarriage among North Indian women.

This study investigated the association of common polymorphisms of the endothelial nitric oxide synthase (eNOS) gene with recurrent miscarriage (RM) among North Indian women. A total of 200 patients with unexplained recurrent miscarriages and 300 controls were genotyped for six polymorphic regions of eNOS by PCR, re-sequencing and RFLP. The GG genotype of 12862A>G, the G allele of Glu298Asp and the aa genotype of intron 4VNTR increased the risk of RM by ∼1.8-fold, ∼3.5-fold and ∼2-fold, respectively (odds ratio (OR) 1.84, 95% confidence intervals (CI) 1.19-2.86, P=0.0066; OR 3.58, 95% CI 2.12-6.03, P<0.0001; and OR 2.23, 95% CI 1.04-4.77, P=0.0493). Two haplotypes were found to have a significant protective effect against RM (OR 0.63, 95% CI 0.48-0.82, P=0.0009; and OR 0.4, 95% CI 0.19-0.81, P=0.0149) and another was found to increase the risk of RM by ∼2-fold (OR 2.12, 95% CI 1.16-3.89 P=0.0195). In conclusion three common polymorphisms of eNOS gene, 12862A>G, Glu298Asp and intron 4VNTR increase the risk of RM in North Indian women. Risk of RM may also be modified by the presence of particular haplotypes.