Vogt-Koyanagi-Harada syndrome (VKH) is a systemic disorder involving many organ systems, including the eye, the ear, the skin, and the meninges. One of the important clinical features of the disease is its strong association with histocompatibility antigens HLA-DR4 and HLA-Dw15. To investigate this association at the DNA level, the polymerase chain reaction technique was used. The DR beta 1 DNA sequence was analyzed to determine which part played the most significant role in the disease process. Although the number of patients studied was small, these data showed that these probes were useful in investigating the HLA-DR subtypes related to VKH. All but one patient (19 of 20) had a specific sequence encoding amino acids 70 and 71 of the HLA-DR beta 1 molecule. The data suggest that the sequence that encodes for amino acids 70 and 71 and adjacent ones of the HLA-DR beta 1 molecule could contribute to disease susceptibility.