TAP1 AND TAP2 POLYMORPHISM IN CELIAC-DISEASE

Coeliac disease is strongly associated with HLA-DQ2, but it is possibl e that additional major histocompatibility complex genes also confer d isease susceptibility. Encoded close to HLA-DQ are two genes, TAP1 and TAP2, whose products are believed to transport antigenic peptides fro m the cytoplasm into the endoplasmic reticulum. Comparison of 81 coeli ac disease patients with caucasoid controls revealed an increased freq uency of the alleles TAP1A and TAP2A in the patient population. Howeve r, no significant difference was found when patients were compared wit h HLA-DR and -DQ matched controls, indicating linkage disequilibrium b etween TAP1A, TAP2A, and HLA-DQ2. The TAP gene products do not have a major influence on susceptibility or resistance to coeliac disease in a Northern European Caucasoid population.