HLA-DRB1*0405 is the predominant allele in Brazilian patients with Vogt-Koyanagi-Harada disease.

Vogt-Koyanagi-Harada (VKH) disease is a rare disorder affecting pigmented structures especially the eye and is the main cause of autoimmune non-infectious uveitis in the Brazilian population. The autoimmune target is believed to be the melanocyte. A strong association of VKH disease with HLA-DR4 in the Japanese population is well known. The same association, albeit with lower relative risks has been found in other populations. A secondary association to HLA-DR1 involving a sequence linked with susceptibility to Rheumatoid Arthritis has also been described. VKH disease is more common in non-Caucasian populations. Brazilian patients of varying ethnic origins have been typed for HLA class II antigens. Several of the features found in other population samples are present. Over half of the patients typed HLA-DR4 (20/37) and typing with sequence-specific oligonucleotides disclosed predominance of the DRB1*0405 allele with a relative risk of 11.76 over the general population. In addition, HLA-DR1 and DQ4 were also present, in patients both positive and negative for HLA-DR4. These results suggest that, as in other autoimmune diseases, multiple overlapping susceptibility factors encoded by the MHC complex contribute to the overall susceptibility for the disease, the major factor however, being the presence of the DRB1*0405 allele.