Endothelial nitric oxide synthase gene 27 bp VNTR polymorphism in intron 4 and its relation with coronary artery disease

ABSTRACT ENDOTHELIAL NITRIC OXIDE SYNTHASE GENE 27 bp VNTR POLYMORPHISM IN INTRON 4 AND ITS RELATION WITH CORONARY ARTERY DISEASE Atherosclerotic coronary artery disease (CAD) is the leading cause of death for both women and men in all over the world as well as in our country. In addition to environmental factors, more and more studies are recently focused on gene-environment and gene-gene interactions in the pathogenesis of coronary atherosclerosis. The aim of our study was to identify whether the endothelial nitric oxide synthase (eNOS) gene, responsible from the synthesis of nitric oxide that has recently been shown to have anti-atherogenic features, 27 bp polymorphism in intron 4 associated with CAD. Moreover some of the risk factors in the pathogenesis of CAD were also investigated. The study population were selected among the patients admitted to the Department of Cardiology of our hospital who underwent coronary angiography. A total of 266 subjects [(133 with CAD (+) and 133 control subjects who doesn't have CAD)] were enrolled in the study. All lipid profile were measured. Patients with CAD had higher values of total cholesterol, LDL-cholesterol and triglycerides (p < 0.05). There were no statistically significant difference for the high density lipoprotein cholesterol between groups. DNA was extracted from the peripheral leukocytes and amplified by PCR then genotypes and frequency of alleles of eNOS were determined. Among the study population, the frequencies for the eNOS genotypes aa, ab and bb were 2.3%, 30.8% and 66.9% respectively. The frequency of allele a was significantly higher in the patients with CAD (p < 0.05). Also in patients with CAD, the sum of aa and ab genotypes were significantly higher than the control group (p < 0.05). According to our genetic data we suggest that the eNOS gene 27 bp VNTR polymorphism in intron 4 in Çukurova region is a associated with the development of CAD. Key words : Coronary artery disease, endothelial nitric oxide synthase gene, polymorphism.