The relationship between coronary artery ectasia and eNOS intron 4a/b gene polymorphisms

Background Little is known about the pathogenesis and genetics of coronary artery ectasia (CAE). We studied eNOS gene intron 4a/b polymorphism in this patient population. Methods The study group included 30 patients with non-obstructive CAD besides CAE on coronary angiogram performed due to positive non-invasive diagnostic test results. The control group included 20 patients with normal coronary arteries. Agarose gel electrophoresis was used to identify eNOS gene polymorphisms. Results Only one coronary vessel was involved in most of the study cohort and the left anterior descending artery (LAD) was the most frequently involved vessel. The frequencies of eNOS gene phenotypes in the CAE group were 3.3% for "aa", 53.3% for "ab" and they were higher than in the control group. However, statistical significance was not reached (X-2=5.10, P=0.08). When compared with the control group the presence of"a"type allele of eNOS gene was significantly more frequent in the CAE group (X-2=4.88, P=0.027). By univariate analysis, eNOS gene polymorphism was correlated with CAE but this significance was attenuated after additional adjustment for potential confounding. Conclusion Patients who have the "a" type allele of the eNOS gene may have an increased risk for CAE.