Fine-mapping of the type 1 diabetes locus (IDDM4) on chromosome 11q and evaluation of two candidate genes (FADD and GALN) by affected sibpair and linkage-disequilibrium analyses.
A gene encoding a novel transmembrane protein was identified by DNA sequence analysis within the insulin-dependent diabetes mellitus (IDDM) locus IDDM4 on chromosome 11q13.
The method is applied to affected-sib-pair data, and the joint effects of IDDM1 (HLA) and IDDM2 (the INS VNTR) and of IDDM1 and IDDM4 (FGF3-linked) are assessed with relation to the development of IDDM.
Our study also revealed evidence for an IDDM locus on chromosome 11q13 (IDDM4) using affected siblings (P = 0.0043), but no evidence using discordant siblings.