Excess of DD homozygotes in haemodialysed patients with type II diabetes. The Diabetic Nephropathy Study Group

The role of the insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene in the genesis of diabetic nephropathy hasbeen controversial. It has recently been proposed that progression occursmore rapidly in individuals with diabetic and non-diabetic renal diseasewho are homozygous for the D allele. We studied 658 patients with type IIdiabetes, 347 without diabetic nephropathy and 311 with various stages ofdiabetic nephropathy, and determined the I/D polymorphism of the ACE gene.Patients at the extremes of renal risk, i.e. normotensive patients withoutantihypertensive treatment and without nephropathy (n = 144), vs patientson dialysis (n = 61), differed with respect to genotype (DD 36.8% vs 57.4%;P = 0.007) and allele frequencies (D 0.59 vs 0.76; P < 0.001). Incontrast, patients with and without presumed nephropathy as assessed byalbuminuria did not differ with respect to DD genotype. In conclusion, inthis study, which was limited by sample size, patients with the highestrenal risk more frequently had the DD genotype. This would be compatiblewith a greater risk of (or rate of) progression to end-stage renal failure.