ASSOCIATION OF ACE GENE POLYMORPHISM AND DIABETIC NEPHROPATHY

In patients with type 1 diabetes an association has been found between an insertion/deletion (I/D) polymorphism in the gene for angiotensin I converting enzyme and the presence of diabetic nephropathy. Our objective was (i) to assess this association in a large cohort of patients with type 1 diabetes and (ii) to examine whether this finding also applies to type 2 diabetes. We examined 247 patients with type 1 diabetes of more than 10 years duration (135 patients greater than or equal to 20 years): Nephropathy was present in 114 and absent in 133 patients. Furthermore we separately analyzed 455 patients with type 2 diabetes of more than 10 years duration (158 patients greater than or equal to 20 years). Nephropathy was present in 247 and absent in 208 patients. Nephropathy was defined by confirmed presence of albuminuria > 30 mg/day (or > 20 mu g/min). The I/D polymorphism was analyzed with PCR technique and alleles were visualized on 2% agarose gels after ethidium staining. Allele frequencies in the overall diabetic population did not differ significantly from the normal population. Distribution of genotypes was not significantly different between type 1 patients with and without nephropathy (P = 0.377). Also, no significant difference in genotype distribution was found between type 2 diabetic patients with and without nephropathy (P = 0.948). We conclude that no significant association between I/D polymorphism and nephropathy was demonstrable in either type 1 or type 2 diabetes, despite considerable statistical power of the patient sample and adequate duration of diabetes for nephropathy to become manifest.