Analysis of polymorphism in renin angiotensin system and other related genes in South Indian chronic kidney disease patients.

BACKGROUND Several Renin Angiotensin System (RAS) polymorphisms alter the homeostasis to an abnormal state. Similarly, other genes such as Nephrin (NPHS1) and Podocin (NPHS2) contribute to the loss of renal function during renal diseases. In Indian population, studies in RAS and other renal specific gene polymorphisms in Chronic Kidney Disease (CKD) patients are scanty. METHODS We examined 118 CKD patients and 98 control subjects for the occurrence of common polymorphisms in angiotensin converting enzyme insertion/deletion (ACE; I/D), angiotensinogen (AGT; M235T), chymase (CMA; -1903G>A), angiotensin receptor type-1 (AGTR1-1166A>C), methylene tetrahydrofolate reductase (MTHFR; 677C>T), nephrin (NPHS1; R1160X) and podocin (NPHS2; R291W and R229Q). RESULT Significant association was observed in AGT-M235T polymorphism between CKD patients and controls. The frequency of TT genotype was higher in CKD patients when compared with controls (0.39 vs. 0.14; chi(2)=20.3, P<0.001). ACE-DD genotype showed a higher level of systolic pressure with a median of 166 mmHg (P<0.05) when compared to II and ID genotypes. Two heterozygous conditions of NPHS2-R229Q polymorphism were found among 105 CKD patients. No significant associations were found in genotype frequencies in other above polymorphisms between CKD patients and controls. CONCLUSION Asian Indian population with AGT-TT genotypes may have a higher relative risk towards CKD with odds ratio (OR) 3.98 (95% CI=1.92-8.25; P=0.0002).