POLYMORPHISMS OF DMA AND DMB GENES IN JAPANESE SYSTEMIC LUPUS-ERYTHEMATOSUS

Associations between polymorphisms of DMA and DMB alleles and systemic lupus erythematosus (SLE) were studied in 51 Japanese SLE patients an d 77 normal subjects by the polymerase chain reaction-restriction frag ment length polymorphism (PCR-RFLP) method. Phenotype frequencies of D MB0101 tended to increase in SLE, but the difference was not signific ant (76.5% vs 70.1% in controls). The phenotype frequency of DMB0103 was decreased in the SLE group, but the difference was not significant (49.0% vs 53.2%). Furthermore, there was no evidence of any associati on of either DMA or DMB alleles with HLA-DRB11501. The phenotype freq uency of DMB0101 was higher in the SLE group with anti-double-strande d DNA antibody (a-dsDNA) than in the SLE group without a-dsDNA, but th e difference was not significant (P = 0.045, corrected P not significa nt). No other DMA or DMB alleles showed any associations in various im munological subgroups of SLE. These data suggest that neither the DMA nor the DMB gene determines susceptibility to SLE in Japanese.