Implications of I/ D (rs4340) polymorphism in CAD among South Indian population

Abstract

Genetic factors are important in the pathogenesis of coronary artery disease (CAD). The I/D polymorphism in the Angiotensin converting enzyme (ACE) gene is a genetic risk factor for CAD patients who have a history of Myocardial Infraction (MI). We investigated the association between I/D polymorphism of the ACE gene and the presence of CAD in one hundred patients (79 males and 21 females, aged between 21- 82) who underwent diagnostic coronary angiography and compared with one hundred patients-as controls (62 males and 38 females, aged between 20- 72) who had false symptoms of CAD. The presence of risk factors including age, hypertension, hypercholesterolemia, tobacco use, diabetes mellitus and hyperuricemia was also determined. ACE I/D polymorphism was detected by polymerase chain reaction. The D allele frequency was higher (p <0-01) in CAD patients. The logistic regression analysis indicated that the D allele in association with classical risk factors had the potential to induce CAD, with odds ratio = 0.58(95% CI; 0.37-0.90). This study revealed that, the I/D polymorphism of ACE gene (carrying D allele) was found to be an independent risk factor for CAD in the studied South Indian population. The number of risk factors did not alter the frequency of ACE gene genotype among patients with CAD, however, in normotensives, the odds ratio of DD-genotype was significantly higher, as the D allele of ACE gene polymorphism was found to be associated with morbidity in CAD in this study population. Key words: ACE gene polymorphism, coronary artery disease, myocardial infarction, risk factors.