Sir.—In the Pediatric Staff Conference on juvenile arthritis (Journal 1981;135:557-561), John Baum, MD, was asked, "Is there any predictive help of histocompatibility antigens for the occurrence of uveitis?" He replied, "... I don't believe they have shown any correlations with uveitis." However, at the Ross Conference on Pediatric Research in 1979, Nicole Suciu-Foca, PhD, and I presented what is to our knowledge the first report of the association of HLA-DRw5 with pauciarticular juvenile rheumatoid arthritis, in particular with the form of disease that occurs in girls, has a particularly early onset, has a predisposition for the knee, and often gives a positive test result for antinuclear factor and subacute or chronic uveitis.1-3 This was subsequently confirmed by at least three other groups.4-6 In our clinic, 91% of the children with negative results for HLA-B27 and who have uveitis tested positively for HLA-DRw5.3