Diabetic retinopathy and HLA antigens in type 2 diabetes mellitus.

PURPOSE: Diabetic retinopathy is the most common complication of diabetes mellitus. No single predisposing factor has been identified, and genetic factors may play a role in the development of severe retinopathy. In this study, we investigated the association between diabetic retinopathy and HLA antigens in type 2 diabetes mellitus.
METHODS: This study was conducted at the retina unit of the Department of Ophthalmology of Ondokuz Mayis University between October 1999 and March 2000, and included 46 diabetics with non-proliferative retinopathy and 30 with proliferative retinopathy, with 30 nondiabetic controls. HLA class I (A, B, C) antigens were studied by Terasaki's microlymphocytotoxicity test and HLA class II (DR, DQ) typing was carried out using a polymerase chain reaction-sequence specific primer.
RESULTS: HLA-DR4 and DQ8 frequencies were higherin patients with non-proliferative retinopathy than those with proliferative retinopathy, and HLA-DR7 frequency was higher in patients with proliferative retinopathy than non-proliferative cases (p<0.05). No significant differences in HLA antigens were found between patient groups and controls.
CONCLUSIONS: The differences in HLA antigen frequencies between patients with and without proliferative retinopathy suggest a genetic contribution to diabetic retinopathy.