Analysis of the HLA association with rheumatoid arthritis.

Definitive determination of the HLA linked gene or genes for susceptibility to RA will be achieved (1) by the accumulation of an adequate body of data on the haplotype frequencies in a random set of RA patients and controls and (2) by further study of other loci in the DR region, involving the use of DNA probes as well as conventional techniques. Indirect evidence is here put forward to suggest that it may turn out that some part of DR4 specificity itself may be directly involved in increasing susceptibility and that DR1 epitopes may be involved in a similar way.