Pattern of histocompatibility (HLA) antigen distribution among Nigerian (West African black) diabetics

The pattern of HLA distribution was studied in 70 Nigerian diabetics. There was no association at all between HLA-B8 and insulin-dependent diabetes mellitus (IDDM). There was an increased frequency of HLA-B15 in all categories of patients: those with onset before 40 yr, those with onset after 40 yr (P less than 0.05), those with IDDM (P less than 0.05), and those with non-insulin-dependent diabetes mellitus (NIDDM). HLA-B7 was slightly increased in frequency contrary to the findings in Caucasian IDDM. HLA-A10 and HLA-Aw32 were increased in all the groups of patients, while HLA-B17 was higher in those with onset after 40 yr (P less than 0.02) and NIDDM (P less than 0.02). HLA-Bw35 was decreased in all categories of patients. However, all the observed deviations fell short of statistical significance when correction was made for the number of antigens tested for. Comparison of the data with those in other black populations revealed that the over-all pattern of HLA distribution in black diabetics is rather disparate and still relatively ill defined. It is concluded that the pattern of HLA and diabetes association in Nigerian diabetics would appear to be different from that in most other racial groups including North American and South African blacks. There is, however, a need to further study larger numbers of Nigerian diabetics and other black population groups so that a clearer picture may emerge.