[HLA-DR and rheumatoid arthritis in adults. Study on the south of France].

In a homogenous group of 31 cases of adult rheumatoid arthritis treated with gold salts and belonging to a caucasoid race in the South of France, HLA-DR groups were determined. The association with HLA-DR 4 was confirmed. DRw4 was present in 32.2 % of patients as against 12.9 % in 116 controls (p < 0.015). The relative risk of rheumatoid arthritis for DRw4 subjects is 3.3. This association is even more significant statistically in men, in spite of the small number studied (p < 0.005). The frequency of the DRw4 antigen is lower in the South than in the North of Europe (12.9 % as against 24 % respectively). The incidence of the disease and the problems of grouping for HLA-DRw4 and associated antigens are discussed.