Background: Coeliac disease (CD) is an autoimmune condition occurring in genetically predisposed individuals exposed to an environmental trigger. The human leukocyte antigen (HLA) haplotypes HLA-DQ2.5 and HLA-DQ8 have the strongest association with CD, and 90 - 95% of CD patients bear these haplotypes. The susceptibility of the South African (SA) population to CD has not been studied previously.
Objectives: To describe the genetic propensity of the SA population to CD.
Methods: The South African National Blood Service database was used to analyse the prevalence of HLA-DQ2.5 and HLA-DQ8 in potential donors and recipients of organ transplants. Self-reported ethnic group was used to estimate the prevalence among different population groups.
Results: The overall prevalence of HLA-DQ2.5 and HLA-DQ8 was 19.8%. The prevalence was lower in black participants (15.9%) than in whites (28.6%). Coloured (22.0%) and Indian (17.4%) participants had an intermediate prevalence. There was no significant difference between potential transplant donors and recipients.
Conclusions: The prevalence of HLA-DQ2.5 and HLA-DQ8 differed among SA study participants of different ethnicities. However, the notion that CD does not occur in black South Africans owing to lack of a genetic predisposition is incorrect.