PARAOXONASE GENE POLYMORPHISM AND CORONARY-ARTERY DISEASE IN INDIAN SUBJECTS

The human serum HDL-linked paraoxonase enzyme limits the LDL peroxidat ion by preventing transformation of LDL into biologically active ather ogenic particles. Paraoxonase serum activity varies among individuals due to an Gln/Arg polymorphism with low (A phenotype) and high activit y (B phenotype). The present study correlates the paraoxonase enzyme a ctivity and the paraoxonase gene polymorphism among 200 Indians with o r without coronary artery disease (CAD). We analyzed the PON enzyme ac tivity and have identified A and B phenotypes by Alwl restriction mapp ing. In 120 CAD patients, the genotypes A and B constituted 75 and 25% , here as in 80 control subjects, the genotypes A and B constituted 25 and 17%, respectively. The frequency of AB genotype is higher in CAD subjects with or without diabetes, than in controls. Arg allele freque ncy was higher (0.45) in CAD subjects than in controls (0.17). The con ventional risk factors and the family history of CAD did not affect th e genotype frequency distribution among Indians. In conclusion, paraox onase polymorphism may have been involved in the predisposition to CAD through a mechanism other than lipid oxidation. (C) 1998 Elsevier Sci ence Ireland Ltd. All rights reserved.