[HLA-A, B, C, and DR typing in rheumatoid polyarthritis]

HLA-A, B, C typing were performed in 72 caucasians with rheumatoid arthritis. HLA-DR typing were accomplished in 40 patients among these 72 subjects. DR4 was clearly increased with a frequency of 55 p. 100 versus 18 p. 100 in controls. We did not find an association between DR4 and the presence of rheumatoid factor. Clinical and biological signs are similar in rheumatoid arthritis with and without DR4. Two other HLA antigens, B40 and Cw3, were increased and their frequency was twice as high in patients as compared with controls. A synthesis of six studies published in the world confirms the elevation of B40 in this disease and later on suggests the elevation of Cw3 which is often linked with B40. The association of rheumatoid arthritis with B40 and Cw3 can be explained by a linkage disequilibrium between DR4 and B40 on the one hand, between DR4 and Cw3 on the other hand.