Endothelial nitric oxide synthase (eNOS) gene Glu298Asp polymorphism and expression in North Indian preeclamptic women.

Abstract

Pathophysiological processes in preeclampsia (PE) are influenced by genetic factors, nitric oxide synthases seem to play important roles, although their expression in and their role is still unclear. To better characterize the host genetic factors determining the susceptibility to PE, we evaluated the influence of polymorphisms (Glu298Asp) in the endothelial nitric oxide synthase (eNOS) gene on the risk of developing PE by checking the expression level. We conducted a hospital-based case-control study including 300 women with preeclampsia and 200 healthy pregnant women. Their blood samples were analyzed for levels of nitric oxide, eNOS gene polymorphism and expression. eNOS mRNA levels were determined using RT-PCR and expressed as arbitrary units after correction with control β-Actin gene mRNA levels. The mRNA expression of eNOS gene was found to be significantly lower in blood (P<0.05) from women with PE compared to that from normal pregnancies. The total nitric oxide levels (P<0.001) were decreased in study Group as compared to healthy pregnant patients. The intergenotypic variation of nitric oxide levels in preeclamptic women was found to be significant (P<0.001). These results indicate the relationship between reduced nitric oxide levels and eNOS gene polymorphism leading to its altered expression in preeclamptic women.