An interleukin 1B allele, which correlates with a high secretor phenotype, is associated with diabetic nephropathy

Induction of interleukin 1 activates vascular endothelial and kidney mesangial cells, and increases production of type IV (basement membrane) collagen. Hence, genes within the interleukin 1 gene cluster are potential candidates in the pathogenesis of diabetic nephropathy, In a previously validated case-control study from Northern Ireland, consisting of 95 patients with insulin-dependent (type 1) diabetes and nephropathy (cases) and 96 patients with insulin-dependent (type 1) diabetes without nephropathy (controls), the authors performed PCR-based genotyping of specific DNA polymorphisms within the interleukin IA, interleukin 1B, interleukin 1 (type 1) receptor and interleukin 1 receptor antagonist genes, The groups were matched for age at onset and duration of diabetes. A statistically significant increase was found in the allele frequency of the interleukin 1B*2 allele in cases compared to controls (chi(2) = 7.19, df. = 1; P = 0.007, Pcorr = 0.028). The results of this study suggest that the interleukin 1B*2 allele, or a susceptibility factor in linkage disequilibrium with this allele, is associated with diabetic nephropathy in the Northern Ireland population. (C) 1998 Academic Press.