The role of ATP-binding-cassette-transporter-A1 (ABCA1) gene polymorphism on coronary artery disease risk

ATP-binding cassette transporter A1 (ABCA1) plays a pivotal role in intracellular cholesterol removal and exerts a protective effect against atherosclerosis. The role of genetic factors in susceptibility to coronary artery disease (CAD) is not clear. The aim of this study was to evaluate for the first time the possible association between R219K gene polymorphism and coronary artery disease in an Iranian adult population. A total of 207 consecutive patients with CAD (group A) and 94 patients without CAD (group B) were studied. We determined the presence of the R219K variant in the ABCA1 gene by polymerase chain reaction (PCR) and restriction analysis in 301 patients with and without CAD. The distribution of genotypes among the 2 groups was significantly different (P=0.009). In univariate analysis (with genotype AA as reference), the GG genotype was associated with a significantly increased risk of CAD (P=0.002; odds ratio [OR]=2.761; 95% confidence interval [CI]=1.418-5.374), but the GA genotype did not show a significant association (P=0.234) (data not shown). A multivariate logistic regression analysis (using sex as clinically significant variable, and using age, diabetes mellitus, low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein [HDL], smoking, body mass index [BMI], and genotype as statistically significant variables) was used to determine independent associations and adjusted ORs. The GG genotype (compared with the AA genotype) was an independent predictor of CAD (OR=2.856, 95% CI=1.307-6.241; P=0.009), followed by BMI (P=0.034; OR=1.100; 95% CI=1.007-1.200). The GG genotype in the ABCA1 gene is independently associated with CAD in Iranian patients.