The distribution of HLA-DPB1 alleles was studied in 94 adult Caucasian
RA patients (65 = seropositive, 29 = seronegative) and 40 normal cont
rols. The DPB1 alleles were defined by oligonucleotide typing of polym
erase chain (PCR)-amplified genomic DNA. The prevalence of the DPB104
02 allele was higher in seropositive RA patients and DPB10201 was hig
her in seronegative RA patients. These differences were not significan
t, however. It is likely that DPB1 alleles do not play an important ro
le in susceptibility to RA.