Angiotensinogen M235T and chymase gene CMA/B polymorphisms are not associated with nephropathy in type II diabetes

Background. Several studies have suggested that the same genetic factors ma y be involved in the predisposition to both essential hypertension and diab etic nephropathy, but the molecular mechanism underlying this predispositio n still remains unclear. In particular, the role of genes involved in blood -pressure regulation and angiotensin II action is still controversial. This study examines a possible association between angiotensinogen M235T and ch ymase gene CMA/B polymorphisms with the presence of nephropathy in type II diabetic Caucasians. Methods. For the purposes of the study, 323 microalbuminuric and 127 overt proteinuric cases, together with 243 normoalbuminuric controls with long-du ration diabetes were selected from a group of 941 type II diabetic patients with established renal status. Results. No differences in the genotype distributions or allele frequencies of the examined polymorphisms between the study groups were observed. The study groups were also stratified by gender, diabetes duration, level of gl ycaemic control, body mass index, hypertension, and retinopathy status, but still no distortion in the distributions of genotypes of any of the examin ed polymorphisms in any of the strata was shown. Conclusions. Our study provided evidence against an association between ang iotensinogen M235T or chymase gene CMA/B polymorphisms and the presence of incipient or overt nephropathy in Caucasian patients with type II diabetes.