Since there are three haplotypes of these amino acid residues in the DPβ chain (84G-85G-86P-87M-96R, 84D-85E-86A-87V-96K, 84D-85E-86A-87V-96R), the results might reflect the effects of the haplotype of 84G-85G-86P-87M-96R on the susceptibility of ACPA(+)RA. The gene discussed is PRTN3; the disease is rheumatoid arthritis.