The difference persists with stratification, at least for DR5(11) and DPB1*0201, suggesting that this effect is unlikely to be due to linkage disequilibrium with HLA alleles known to be associated with early onset pauciarticular JRA.
The frequencies of DNA fragments associated with the following HLA class II genes were increased in PJRA when compared to normal controls: DRB1*08 (DRw8) (35.2% vs 10.3%, RR = 4.6, p less than 10(-3), DRB3*01/02/03 (DRw52) (76.3% vs 48.1%, RR 3.5, p less than 10(-3)), DQA1*0401 (41.0% vs 7.4%, RR = 7.9, p less than 10(-3)), DQA1*0501 (55.6% vs 29.7%, RR = 3.0, p less than 10(-2), DQB1*0301 (DQw7) (46.2% vs 17.5%, RR = 4.0; p less than 10(-2)), DPA1*0201 (44.2% vs 7.9%, RR = 8.7, p less than 10(-5)), and DPB1*02 (DPw2) (40.7% vs 7.1%, RR = 8.5, p less than 10(-6)).