HLA-DRB1-ASTERISK-04 AND DRB1-ASTERISK-14 ALLELES ARE ASSOCIATED WITHSUSCEPTIBILITY TO PEMPHIGUS AMONG JAPANESE

It has previously been demonstrated that susceptibility to pemphigus v ulgaris is associated with human leukocyte antigen (HLA)-DR4 serologic specificity among Ashkenase Jews, and with DR4 as well as DR6 (DR14) in other ethnic groups. We genotyped HLA-DRB1, DQA1, DQB1, and DPB1 al leles in 16 patients with pemphigus by polymerase chain reaction-restr iction fragment length polymorphism, to find evidence of potential HLA class II allele associations with pemphigus in Japanese patients who have a relatively homogeneous ethnic background. All nine patients wit h pemphigus vulgaris and five of seven patients with pemphigus foliace us carried one or two alleles of HLA-DRB104 (*0403, *0406) and HLA-DR B114 (*1401, *1405, *1406) subtypes. Sequence analysis of these DRB1* 04 and DRB114 alleles revealed the amino acid homology of phenylalani ne at position 26 and valine at position 86 with the DRB10402 allele that reportedly confers a strong susceptibility to pemphigus vulgaris in Ashkenazi Jews. Thus our findings, together with previous HLA studi es on pemphigus vulgaris patients of different ethnic groups, suggest that HLA-DRB104 and DRB1*14 alleles are commonly associated with pemp higus vulgaris across racial barriers. These HLA-DRB1 alleles are like ly to be also associated with pemphigus foliaceus. Further studies on more diverse ethnic populations will be helpful in determining the sig nificance of the association between certain amino acid residues of th e class II molecules and disease susceptibility to pemphigus vulgaris as well as pemphigus foliaceus.