Association between T-786C polymorphism of endothelial nitric oxide synthase gene and level of the vessel dilation factor in patients with coronary artery disease

Various polymorphisms on endothelial nitric oxide synthase (eNOs) gene cause reduced production of NO, the endothelial relaxing factor, and may accelerate the process of atherosclerosis. The study designed to investigate the frequency of T-786C polymorphism of the eNOs gene in patients suffering from coronary artery disease (CAD) in north-west of Iran. One hundred twenty subjects including 60 patients with angiographically diagnosed CAD and 60 age and sex matched CAD-free subjects as control were studied. The levels of nitric oxide in the samples were measured with the Griess Method. The genotype studies were carried using allele specific PCR. Comparing with the control, reduced levels of NO were noticed in the patient group (P < 0.05). Statistical analysis showed that the genotype TC associated with risk of CAD (OR=2.50, 95% CI: 1.13-5.50, P=0.023). The prevalence of C allele was significantly higher in patients compared to control group (OR=2.04, 95% CI: 1.16-3.57, P=0.013). The low levels of NO and increased frequency of T-786C polymorphism might be a risk factor in progression of coronary artery disease in the studied subjects.