Angiotensin I-Converting Enzyme Gene Polymorphism and Diabetic Nephropathy in Filipino Type 2 Diabetes Mellitus Patients

Abstract

Objective. Previous studies have demonstrated the role of genetic susceptibility in the pathogenesis of diabetic nephropathy. The study aimed to determine the frequencies of angiotensin I-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in a pilot population of Filipino type 2 diabetic patients and normal controls. Methods. An analysis of the ACE gene polymorphism was performed in 42 diabetic patients with and without nephropathy, and 24 normal controls. The analysis was done using polymerase chain reaction, restriction enzyme digestion, and gel electrophoresis techniques to determine the polymorphism (II, DD or ID). Independent T-tests and chi-square tests were used to compare clinical characteristics, and logistic regression analysis was done to determine odds ratio for development of nephropathy. Results. The ID polymorphism of the ACE gene was more frequent (52.4%) in patients with diabetic nephropathy (n=21). In those without nephropathy (n=21), II was more common (61.9%). ID was the more frequent genotype in the normal controls (n=24) (58.3%). The odds of developing diabetic nephropathy were increased by 4.8 times in those with ID polymorphism, and 2.9 times in those with DD. Conclusion. The D allele was more common in patients with diabetic nephropathy, similar to the observation in South Indian patients. Since the study involved only a small pilot group, studies on a larger population is needed to establish the hypothesized role of the D allele in susceptibility to diabetic nephropathy in Filipinos.