Contribution of REN gene MBbo I polymorphism in conferring risk for essential hypertension: a case control study from South India.

Renin is a rate-limiting enzyme of the renin-angiotensin-aldosterone system (RAAS) that plays a crucial role in the regulation of blood pressure. The renin gene has been suggested as a marker for genetic predisposition to essential hypertension (EHT) in humans. The purpose of the study is to explore the association of a genetic marker of renin gene Mbo I polymorphism with EHT in the South Indian population. A total of 279 hypertensive and 200 normotensive subjects were genotyped for REN Mbo I polymorphism (RFLP) using the PCR-restriction fragment length polymorphism method. There were no significant differences in the distribution of genotypes and alleles for REN gene Mbo I polymorphism between hypertensive cases and controls (p>0.05). The genotypic and allele frequencies were in Hardy-Weinberg equilibrium both in cases and controls. Females with Mbo I AA+GA genotypes had 1.87-fold higher risk to develop hypertension as compared with those with GG genotype (odds ratio 1.87; 95% confidence interval = 0.98-3.56, p = 0.057). Our results indicate that renin gene Mbo I site polymorphism is not associated with blood pressure levels and risk of hypertension. However, the present study demonstrates risk for females who are carriers of REN Mbo I A allele for developing essential hypertension.