The -T786C Polymorphism in the 5 Flanking Region of the Endothelial Nitric Oxide Synthase Gene as a Biomarker in Iranian Population with Coronary Artery Disease

Background and Endothelial-derived nitric oxide (NO) is a major contributor in regulating myocardial function and has been implicated in development of coronary artery disease (CAD) as the most common type of cardiovascular disease. It is synthesized in the human body from L-arginine by constitutive endothelial NOS (eNOS) as one out of three known isoforms of NO synthase (NOS) involved in this process. Based on recent studies, single nucleotide polymorphisms (SNPs) of some genes, such as eNOS, appear to be genetic risk factors for CAD; however, the results are inconsistent across different ethnic populations. Therefore, the current study was carried out to assess the association between -786T/C polymorphism (rs2070744) and susceptibility to CAD risk in Iranian population. The study included 50 patients with angiographically confirmed CAD (≥50% stenosis in at least one coronary vessel) and 100 aged-matched individuals without cardiovascular background, hypertension, diabetes, or any other specific illness. The genomic DNA was extracted from peripheral blood cells and genotyping was performed using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The frequency of risk allele (C) was significantly higher in case group compared to control group (P= 0.04). According to the findings, the presence of the C allele was associated with 1.67-fold increased risk of CAD compared with individulas lacking the risk allele (95% CI= 1.01-2.73, P= 0.04). Several studies revealed association of -T786C polymorphism with coronary spasm, myocardial infarction, hypertension, and multivessel CAD in different populations. In current study, a possible association was found between -T786C polymorphism and risk of CAD, which is in line with previous findings. These results suggest this variation as a predictor marker for estimating the risk of CAD in Iranian population.