Polymorphisms in the 5′-Flanking Region of the Insulin Gene and Non-Insulin-Dependent Diabetes

Abstract
DNA insertions in the 5''-flanking region of the insulin gene were studied by Southern blot hybridization techniques using a cloned gene probe in 159 unrelated caucasians. Subjects homozygous for a large DNA insertion at this locus had a higher risk of concurrence of non-insulin-dependent diabetes (NIDD) than controls (P < 0.01). Analysis of a single large NIDD predigree (n = 67 in 4 generations; 11 diabetic subjects) showed no linkage between the size of DNA inserts and diabetes (Lod score = -5.7), suggesting a separate diabetogenic locus (or loci) in this family.