NO ASSOCIATION OF CONVERTING-ENZYME INSERTION DELETION POLYMORPHISM WITH IMMUNOGLOBULIN-A GLOMERULONEPHRITIS

has been recently reported that in type 1 diabetes the insertion/delet ion (I/D) polymorphism of the angiotensin l-converting enzyme gene is associated with the presence of diabetic nephropathy, Tissue angiotens in I-converting enzyme is determined by I/D polymorphism, and it has b een speculated that in diabetes differences of local angiotensin II av ailability determine the risk of renal disease, Since angiotensin II i s thought to play an important role in the evolution of renal disease in general, we tested whether genotype distribution of the I/D polymor phism is also different in patients with immunoglobulin A-glomerulonep hritis (IgA-GN). Furthermore we compared IgA-GN patients with (1) stab le renal function or (2) terminal renal failure to investigate a poten tial role of the I/D polymorphism in the renal prognosis, We examined 122 patients with biopsy-confirmed IgA-GN who had stable renal functio n and 82 dialysis-dependent or transplanted patients with biopsy-confi rmed IgA-GN, Furthermore, in 134 healthy individuals used as controls we analyzed the DNA for normal distribution of genotypes and allele fr equencies, The polymorphic region was amplified using polymerase chain reaction with specific primers. Alleles were detected on 2% agarose g els, Genotype distributions and allele frequencies were not significan tly different between controls and patients with IgA-GN and stable ren al function, Furthermore, no significant difference in genotype distri bution was detected between patients with IgA-GN and stable renal func tion compared with patients with IgA-GN and end-stage renal failure, a lthough a trend for a higher frequency of DD-homozygotes was noted in the latter group (P = 0.07), We conclude that the genotype distributio n of the I/D polymorphism is not changed in IgA-GN. To firmly establis h whether it is related to the risk of progression, further studies wi th larger patient samples are required. (C) 1995 by the National Kidne y Foundation, Inc.