Pon1 (Paraoxonase 1) Q192R gene polymorphism in ischemic stroke among North Indian population

Abstract

PON1 is an HDL-associated esterase, two common polymorphisms in the PON1 gene, the Q192R and L55M substitutions, determine inter-individual variation in PON1 activity. The association of these polymorphisms with the risk of Ischemic stroke remains controversial. Hence, the role of PON1 Q192R gene polymorphism in Ischemic stroke was studied in North Indian Population. In the present study, the PON1 Q192R gene polymorphism was analyzed in Ischemic stroke patients (n-63) and age, sex and geography matched healthy controls (n-63) through PCR-RFLP method. Ethical clearance was obtained from Ethics committee for Human Research, Lady Hardinge Medical College, New Delhi. In the present study, distribution of PON1 Q192R gene polymorphism was not seen to differ between cases and controls. Unadjusted odds ratio analysis showed that RR genotype was found to pose 3.07 fold (CI = 0.30-30.67) increased risk for Ischemic stroke, albeit with no statistical significance (p = 0.34). The R allele was also found to pose 1.077 fold (CI = 0.50-2.29) increased risk for Ischemic stroke, albeit with no statistical significance (p = 0.847). After adjustment for conventional vascular and prothrombotic risk factors, odds ratio analysis revealed that both RR genotype [OR-0.153 (0.012 - 1.898), p = 0.144] and R allele [OR-0.932 (0.349 - 2.492), p = 0.888] posed reduced risk for Ischemic stroke, albeit with no statistical significance. Our study suggests the possible role of R allele of PON1 Q192R polymorphism as genetic risk factor when presented simultaneously with other known traditional risk factors of Ischemic stroke. Further studies are necessary before PON1 Q192R gene polymorphism can be considered as genetic risk factor for Ischemic Stroke.