HLA Genotypes and the Increased Incidence of Coeliac Disease in Sweden

Background: A strong increase of childhood coeliac disease (CD) was found in Sweden concurrently with changes in the infant feeding pattern. We investigated whether this increase reflects a recruitment of individuals with less predisposing HLA genotypes. Methods: Genomic HLA-DRB1, -DQA1, and -DQB1 typing was performed in 135 Swedish patients (48 belonging to a low- and 81 to a high-incidence cohort) and 179 controls. The distribution of HLA class-II genotypes in the cohorts was compared. Results: DQA1*0501 and DQB1*02 conferred increased risk for CD, and a gene dosage effect of DQB1*02 was found. The distribution of HLA genotypes among the cohorts did not differ. Conclusions: The results suggest that Swedish CD patients do not differ in genetic susceptibility compared with other populations. No evidence was found suggesting that the increase would be a result of more frequent development of disease in individuals carrying less predisposing HLA genotypes.