In the German, Italian and Thai population, the extended haplotype (EH) HLA-C*06-B57-DRB1*0701-DQA1*0201-DQB1*0303, named according to the B allele EH-57.1, was reported to be highly overrepresented in patients with psoriasis (Schmitt-Egenolf 1996; Choonhakarn et al. 2002). Here, HLA-DRB1 is linked to psoriasis.