Association of human leucocyte-DR and DQ antigens in coeliac disease: A family study

Background and Aims: No family studies regarding the association of coeliac disease with the human leucocyte antigen (HLA)-DQ locus are available. Mor eover, no HLA studies have been carried out in coeliac disease patients fro m India. The aim of this study was to study the HLA class II (DR and DQ) an tigens in children with coeliac disease and in their first-degree relatives . Methods: Fifteen children with coeliac disease and their first-degree relat ives (birth parents of all the coeliac disease patients and fifteen sibling s) were studied. A group of 123 healthy unrelated and ethnically matched su bjects were used as controls. The HLA-DR and -DQ typing was carried out by a complement-dependent microlymphocytotoxicity assay. The transmission dise quilibrium test was used for analysis of results. Results: There was no association of coeliac disease with DR phenotypes. Ni nety-three per cent of patients (14/15) carried the DQ2 allele. DQ2 was tra nsmitted in 15 of 19 informative cases (transmission probability of 79%, ch i(2) 6.368 with 1 df, nominal P = 0.012 and P value corrected for multiple test = 0.035). The haplotype relative risk associated with DQ2 was 5.71 (95 % confidence interval 1.71-16.28). Conclusion: Coeliac disease in Indian children is predominantly associated with HLA-DQ2. (C) 2000 Blackwell Science Asia Pty Ltd.