HLA Genotypes and the Increased Incidence of Coeliac Disease in Sweden

Abstract
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. 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. 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. 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.