HLA and rheumatoid arthritis. A study of five families

Abstract
Five families with 2 or more members ill with rheumatoid arthritis were investigated clinically. Tissue typing for HLA A, B, C and D/DR antigens was performed. Any HLA haplotype associated with disease could not be defined within these families. The prevalence of the haplotypes containing HLA-DR4 was high, suggesting a direct relationship between DR4 and increased risk of contracting rheumatoid arthritis.