Specific histocompatibility antigens associated with Behçet's disease

We studied the distribution of HL-A antigens in 44 patients with Behcet's disease and in 78 normal control subjects. The antigen frequencies of HL-A5 and 4c were significantly increased in the patients (HL-A5: chi2=22.1, P less than 0001; and 4c: chi2=26.9, P less than .0001).