English

Abstract

BACKGROUND Coronary artery disease is multifactorial in origin. Coronary artery disease predisposition is attributed to genetic factors also. Many gene polymorphisms are implicated out of which paraoxonase 1 (PON 1) gene is an important one. The product of paraoxonase gene is paraoxonase enzyme which is seen in serum associated with high density lipoprotein (HDL). This enzyme is mainly synthesised by the liver. The protective effect of HDL is attributed to the presence of such enzymes on it. Gln to Arg polymorphism at position 192 confers a risk of developing atherosclerosis and coronary artery disease (CAD). This study is done to assess the genotype distribution of PON 1 gene in CAD patients compared to healthy controls in a population from Kerala. METHODS The case group consists of 100 angiographically proven CAD patients with no history of hypertension, diabetes mellitus, hepatic disease or smoking. The control group had 100 healthy controls from the general population. PON 1 gene was amplified by a polymerase chain reaction (PCR) technique already reported and restriction fragment length polymorphism by the restriction enzyme Alwl was done to assess the polymorphism. to assess the polymorphism. RESULTS In this study, the frequency of heterozygous genotype QR was 86 % in control and 76 % in cases. Though there was no significant difference in allele distribution of Q or R, RR genotype was significantly higher in the case group ( 2 = 8.82; p value = .012). With binary logistic regression model, adjusting for age and sex, RR genotype is independently associated with CHD. Adjusted odds ratio of RR was 5.24 with 95 % confidence interval (CI) 1.41 - 19.47 for developing CHD (p < 0.05). CONCLUSIONS The RR genotype is more frequently seen in CAD patients than in controls. The QR genotype is more frequent than QQ or RR in both cases and controls. KEYWORDS Coronary Artery Disease, Paraoxonase, Gene Polymorphism