We found that HLA-B*51 (P = 4.11 × 10−41, OR [95% CI] = 4.63[3.66-5.85]) and B*15 confer risk for BD (P = 2.83 × 10−2, OR [95% CI] = 1.75[1.08-2.84]) in Iranian, and in B*51 negative individuals, only the B*15 allele is significantly associated with BD (P = 2.51 × 10−3, OR [95% CI] = 2.40[1.37-4.20]). The gene discussed is HLA-B; the disease is Behcet disease.