Previous studies have shown that HLA-DRB1*0301 and DQA1*0501 are associated with susceptibility to Graves' disease. Ninety Danish patients with early onset of Graves' disease and 102-192 controls were analyzed for HLA-DR and -DQ to investigate if the same associations exist in the juvenile form of Graves' disease. Both DRB1*0301 and DQA1*0501 were highly significantly increased in the patients with relative risks of 8.0 and 4.6, which are higher than those seen in adults. Stratification showed that DRB1*0301 is more strongly associated than DQA1*0501. Surprisingly, the DRB1*0701,DQA1*0201 haplotype was completely absent from this group of patients, indicating a strong protective role of this haplotype in juvenile Graves' disease.