HLA-DMA and DMB genotyping in patients with rheumatoid arthritis

Objective. To investigate the relation of HLA-DMA and DMB alleles to the development of rheumatoid arthritis (RA). Methods. We studied HLA-DMA and DMB alleles in 153 patients with RA and 138 healthy controls using the amplification created restriction site method and digestion with restriction enzymes. Results. There was no significant difference in frequencies of HLA-DMA and DMB alleles between patients with RA and controls. The HLA-DMA and DMB alleles were not related to extraarticular involvement, seropositivity for rheumatoid factor, or bone erosion. There was also no significant difference in frequencies of HLA-DMA and DMB alleles among DR4-positive and DR4-negative patients and controls. Conclusion. HLA-DMA and DMB do not appear to be associated with the pathogenesis of RA.