Dr, C4, and BF allotypes in juvenile rheumatoid arthritis

HLA-DR, C4, and Bf typing was performed in 99 patients with juvenile rheumatoid arthritis (JRA). DR1 was found with higher frequency in patients with polyarticular JRA than in controls (P < 0.05). DR3 was more common in patients with fever and/or rash than in those without these manifestations (P < 0.05). A significant negative association between JRA and C4A6 (P < 0.05), C4BQ0 (P < 0.0005), and BfF1 (P < 0.05) was found. It is possible that a disequilibrium between DR and C4/Bf genes plays a role in the pathogenesis of JRA.