In this study, by comparing all the aligned DRB1*04 allele sequences, we identified new variations that may be related to RA susceptibility and resistance throughout the whole gene regions including a previously “undetermined region.” Within the group of DRB1*04 alleles certain shared epitopes at AA 70–74 have been associated with RA susceptibility (QRRAA, QKRAA) or resistance (QRRAE). The gene discussed is HLA-DRB1; the disease is rheumatoid arthritis.