The renin-angiotensin system (RAS) genes polymorphism have been associated with blood pressure (BP) response to antihypertensives drugs and may also influence the variability in visit-tovisit BP. Here we have investigated the association of RAS gene polymorphism with response to three classes of antihypertensive drugs (atenolol, amlodipine and enalapril) and also with genetic factor which may influence the variability in visit-to-visit BP. Total of 230 participants of south Indian ethnicity under the medication of any of these three classes of drugs were enrolled. The four polymorphisms analyzed were AGT M235T (rs699), ACE I/D (rs4340) and G2350A (rs4343) and AT1R A1166C (rs5186) were genotyped in all patients and were analyzed for association. Significant association with visit-to-visit variance in BP was found in ACE G2350A variant with the diastolic blood pressure (DBP) and a high significance was observed in AT1R A1166C variant with both systolic blood pressure (SBP) (p < 0.001) and DBP (p < 0.001). Further, we did not observe any significant association between drug response and RAS gene polymorphisms. The present study revealed significant association of visit-to-visit BP variability with ACE G2350A and AT1R A1166C polymorphisms in essential hypertensive subjects. However, results need to be replicated in larger population.
Keywords: A1166C, G2350A, hypertension, Insertion/Deletion, M235T, polymophism, RAS.