Stangl K, Cascorbi I, Laule M, Klein T, Stangl V, Rost S, Wernecke KD, Felix SB, Bindereif A, Baumann G.
High CA repeat numbers in intron 13 of the endothelial nitric oxide synthase gene and increased risk of coronary artery disease.
Pharmacogenetics. 2000 Mar;10(2):133-40.
Endothelial nitric oxide synthase (eNOS) plays a key role in vascular homeostasis. Because its product, nitric oxide, possesses vasodilatory and antiatherogenic properties, an altered eNOS function might promote atherosclerosis. We investigated the association between variations in CA repeat copy number [(CA), polymorphism] in intron 13 of the eNOS gene and the risk of coronary artery disease. (CA), polymorphism was investigated in 1,000 consecutive patients with angiographically confirmed coronary artery disease and 1,000 age- and gender-matched control subjects by a PCR-based fragment length calculation. Twenty-eight different alleles were identified containing 17-44 CA repeats. The presence of one allele containing > or = 38 repeats was associated with an excess risk of coronary artery disease (odds ratio 1.94, 95 percent confidence interval 1.31-2.86, P = 0.001). Carriers of alleles containing > or = 38 CA repeats were, in particular, overrepresented in the subgroup without common cardiovascular risk factors (odds ratio 3.39, 95 percent confidence interval 1.30-8.86, P = 0.009). Logistic regression analysis revealed that the (CA), polymorphism proved to be an independent risk factor (relative risk 2.17, 95 percent confidence interval 1.44-3.27, P = 0.0002). Our findings indicate that high numbers of CA repeats in intron 13 of the eNOS gene are associated with an excess risk of coronary artery disease.