Association of class II HLA antigens and insulin-dependent diabetes mellitus in the population of Vojvodina

Abstract

Class II HLA antigens were investigated in a group of 28 patients with insulin-dependent diabetes mellitus (IDDM) and 218 healthy unrelated persons (control group) from Vojvodina. We used a modified two-colour immunofluorescence method (serologic technique) to determine the phenotype of DR and DQ locus HlA antigens. Phenotype frequencies of class II HLA antigens were determined in both investigated groups and were used for calculating relative risk (RR). If RR was higher than 1, we calculated the population attributable risk (EF), and if RR was lower than 1, we calculated the preventive fraction (PF). Investigation of statistically significant differences in frequencies of class II HLA antigens in patients and control group was performed by using chi 2 test. Results of investigation showed that values of RR were higher than 1 for HLA DR4 (2,808), DR10 (1,116) and DQ3 (1,386), while we noticed a statistically significant difference in frequencies of HLA DR4 (chi 2 test: 4,805) in patients regarding control group. HLA DQ1 antigen has a preventive role in development of IDDM due to highest value of PF (0,314). Results of our investigation confirm that there is an association of HLA DR4 with IDDM in population of Vojvodina. High values of relative risk of IDDM, noticed in persons with HLA-DR4 antigen, point to the degree of risk of IDDM, which is a disease with great socioeconomic importance in Vojvodina.