ANALYSIS OF THE HLA-DR GENE-FREQUENCIES IN JAPANESE CASES OF JUVENILES RHEUMATOID-ARTHRITIS AND RHEUMATOID-ARTHRITIS BY OLIGONUCLEOTIDE DNATYPING

HLA-DR gene frequencies in 59 Japanese children with juvenile rheumato id arthritis (JRA) and 62 Japanese,adults with rheumatoid arthritis (R A) were analyzed by oligonucleotide DNA typing. As in other studies, t he frequency of DRB10405 in RA patients was significantly higher than in the Japanese controls. In a comparison of non-classified JRA patie nts with Japanese controls, no significant differences were observed i n the frequency of DR types. However, when the JRA patients were class ified into four clinical types, i.e., a rheumatoid factor-positive [RF (+)] polyarticular type, a rheumatoid factor-negative [RF(-)] polyarti cular type, a pauciarticular type, and a systemic onset type, DRB1040 5 was found to be significantly higher in the RF(+) polyarticular JRA patients than in the controls (P < 0.05). Thus, the RF(+) polyarticula r type of JRA had the same HLA association as RA. This result is consi stent with the fact that both RF(+) polyarticular JRA and RA cases hav e a similar clinical course.