INSULIN GENE POLYMORPHISM AS A MARKER FOR DIABETES-MELLITUS

A significant association has been reported in Caucasians between the Class 1 (L) allele of the insulin gene and insulin-dependent diabetes mellitus (IDDM) on the one hand, and between the Class 3 (U) allele of the insulin gene and non-insulin-dependent diabetes mellitus (NIDDM) on the other. However, there is a considerable disagreement on this in some populations. In an attempt to study possible associations between insulin alleles and IDDM and NIDDM in Saudis, we investigated the insulin gene polymorphism in non-diabetic and diabetic patients. The frequency of the 3/3 and 1/1 genotypes were significantly higher in the IDDM patients compared with non-diabetic individuals and NIDDM patients. No significant differences were encountered between the NIDDM patients and non-diabetic individuals. The allele frequencies showed no differences between IDDM and NIDDM patients and non-diabetic controls. These results outline the marked genetic variations in the Saudi population and evaluate these findings in the light of those reported for other populations.