Insulin and apolipoprotein A-1/C-III gene polymorphisms relating to hypertriglyceridaemia and diabetes mellitus.

Two gene specific probes have been used to identify polymorphic DNA loci on chromosome 11 close to the insulin and apoprotein A-1 genes in a genetic analysis of hypertriglyceridaemic patients with and without co-existing diabetes. Of the 45 patients studied with both probes, 15 were diabetic of whom nine possessed class 3/3 insulin polymorphism genotypes, compared with none in the non-diabetic group (p less than 0.001; chi 2 test). In contrast, an uncommon apolipoprotein A-1 polymorphism was found to be equally distributed in the diabetic and the non-diabetic patients. No co-segregation of these two particular genetic polymorphisms was found in either patient group. The differing associations of the two disease-related polymorphism genotypes in patients with hypertriglyceridaemia with or without co-existing diabetes may possibly reflect differing aetiologies of the hyperlipidaemia.