The T-786C endothelial nitric oxide synthase genotype is a novel risk factor for coronary artery disease in Caucasian patients of the GENICA study

Objectives We investigated the association of polymorphisms in the promoter region and exon 7 endothelial nitric oxide synthase (eNOS) gene with coronary artery disease (CAD). Background Endothelial dysfunction foretells cardiovascular events and can be genetically determined. Methods We genotyped for the promoter (T-786C) and exon 7 (Glu298Asp, G894T) polymorphisms in 1,225 subjects; 1,106 were consecutive patients undergoing coronary angiography and 119 control subjects without any cardiovascular risk factors. Genotyping was performed with melting curve analysis of polymerase chain reaction products from allele-specific acceptor and donor probes that were 5′- and 3′-end labeled with LCRed640 and fluorescein, respectively; CAD was assessed by quantitative coronary angiography. We performed multiple logistic regression analysis for the effect of the T-786C, the missense Glu298Asp variant, and other coronary risk factors on two- and three-vessel CAD. Results The overall genotype distribution of T-786C (CC = 17.7%, CT = 40.4%, and TT = 41.9%) and Glu298Asp (GG = 43.3%, GT = 37.0%, and TT = 19.7%) was consistent with the Hardy-Weinberg equilibrium. The regression analysis showed that the T-786C, but not the missense Glu298Asp variant, significantly predicted CAD, independent of other risk factors. Compared with TT homozygous, subjects carrying the C allele had a significant (p = 0.002) increase in the odds ratio of harboring two- or three-vessel CAD of 1.672 (95% confidence interval, 1.062 to 2.527). A subgroup analysis confirmed this effect of the T-786C polymorphism in men (p = 0.007), cigarette smokers (p = 0.001), subjects older than 60 years of age (p = 0.007), with hypercholesterolemia (p = 0.011), low high-density lipoprotein cholesterol (p = 0.006), and overweight or with obesity (p = 0.041). Conclusions The C allele at the T-786C endothelial nitric oxide synthase polymorphism is associated with a higher risk of multivessel CAD in Caucasians.