HLA-Bw51 and Behçet's Disease

To the Editor.— Regarding the association of HLA antigens with disease, we have demonstrated that Japanese patients with Behcet's disease have a significantly higher frequency of HLA-B5 than their controls. 1,2 This genetically determined association between HLA-B5 and Behcet's disease was also confirmed among the French, Jewish, Tunisian, and Turkish cases. 3 According to the epidemiologic survey, this disease is known to occur most frequently among the Japanese and Mediterranean populations, where the frequency of HLA-B5 is equally high. Recently it has been shown that HLA-B5 antigen is of a heterogeneous nature and may be divided into at least two subcomponents, HLA-Bw51 and HLA-Bw52. Since HLA-Bw52 is frequent almost equally to the counterpart among the Japanese but rather rare among whites, we suspected that the close association of HLA-B5 and Behcet's disease may be due to that of HLA-Bw52 and this disease. Twelve male and 11 female patients with this