Pemphigus vulgaris in siblings: HLA-DR4 and HLA-DQw3 and susceptibility to pemphigus.

Abstract

The association of pemphigus vulgaris with the HLA serotypes, DR4 and DRw6, and with the DQ-beta chain alleles, DQw1 and DQw3, suggests that there is a genetic predisposition to this disease. However, familial cases of pemphigus vulgaris are exceedingly rare. We studied two siblings with pemphigus vulgaris and three unaffected family members to determine whether an HLA allele was associated with the development of pemphigus vulgaris in this family. We utilized restriction fragment length polymorphism methods using the HLA-DR beta 1, HLA-DQ alpha, and HLA-DW beta 1 genes as cDNA probes. We found that the affected siblings share the haplotype HLA-DR4 and the DQw.3.2 allele. Our findings of gene sharing among siblings with pemphigus vulgaris lend support to previous studies of unrelated Caucasian patients, which implicated DQw3 allele polymorphisms in conferring susceptibility to pemphigus.