Association of cys 311 ser polymorphism of paraoxonase-2 gene with the risk of coronary artery disease.

BACKGROUND Recently another member of the paraoxonase gene family designated paraoxonase-2 has been identified. Paraoxonase-2 has antioxidant properties similar to paraoxonase-1 and paraoxonase-3. However, in contrast to paraoxonase-1 and paraoxonase-3, paraoxonase-2 is not associated with high-density lipoprotein and may only exert its antioxidant function at the cellular level. METHODS We assessed the frequency and genotype distribution of cys 311 ser paraoxonase-2 polymorphism in 300 subjects (>40 years old) with angiographic documentation of coronary artery disease (150 patients with >50% stenosis served as cases and 150 individuals with <20% stenosis served as controls) to determine the possible association between this mutation and susceptibility for coronary artery disease. The paraoxonase-2 genotypes were determined by polymerase chain reaction and DdeI restriction enzyme digestion. RESULTS The cases (coronary artery disease positive patients) showed significant differences in the distribution of cys 311 ser paraoxonase-2 genotypes as compared with the controls (coronary artery disease negative subjects, P=0.015). The analysis of paraoxonase-2 genotypes distribution showed higher percentage of CC genotype among coronary artery disease positive compared with coronary artery disease negative (P=0.008). After controlling for other risk factors, the cys 311 ser polymorphism had not correlation with age, body mass index, gender, smoking, diabetes, level of high-density lipoprotein, low-density lipoprotein, triglyceride, and total cholesterol. CONCLUSION Our data indicate a major effect of the paraoxonase-2 polymorphism on coronary artery disease risk in patients referred to Shariati Hospital in Tehran.