Analysis of polymorphic residues that form the binding pockets of the DRβ1 chain of HLA-DRB1*04 and *14 alleles in pemphigus vulgaris show that they contain similar sequences, as well as in HLA-DRB1*04, *14 and *01 in pemphigus foliaceus. Here, HLA-DRB1 is linked to pemphigus foliaceus.