Disease association studies in 113 EOPA-JRA patients and 207 controls unselected for HLA-DRw8 revealed that the HLA-DRB1*0801, DQA1*0401, DQB1*0402 genotype was associated with a higher relative risk (RR) for disease (RR = 12.8, chi 2 = 48.8, P less than 10(-4)) than was the serologically defined presence of HLA-DRw8 (RR = 8, chi 2 = 39, P less than 10(-4)).
Oligonucleotide typing for alleles of the MHC loci DRB1, DQA1, and DQB1 was performed in 160 patients suffering from EOPA, JCA (or JRA = juvenile rheumatoid arthritis).