HLA-DR and DQ polymorphisms in bullous pemphigoid from northern China.

Bullous pemphigoid (BP) is an autoimmune disease mediated by autoantibodies against hemidesmosome components. This study used PCR-sequence-specific primers to genotype polymorphisms in HLA-DR and DQ in 25 BP patients and 57 normal controls from northern China. We found lower frequencies of DRB1*08 (DR8) and DRB1*08/DQB1*06 (DR8/DQ6) haplotypes in BP patients than in controls (4.08% vs. 15.19% and 1.54% vs. 13.82%, respectively; P < 0.05), suggesting a protective role for DR8 and DR8/DQ6 haplotypes in BP patients from northern China; there were no statistical differences among other alleles tested. This result is strikingly different from previous reports that DQB1*0301 is associated with BP in Caucasian patients and DRB1*1101, DQB1*0302, DRB1*04/DQA1*0301/DQB1*0302 and DRB1*1101/ DQA1*0505/DQB1*0302 with Japanese BP patients. Ethnic differences in the polymorphic composition of the HLA-DR and DQ genes may influence genetic susceptibility to BP.