Genome-wide association studies (GWAS) carried out in Turkey and Japan demonstrated that HLA-B*51, HLA-A*26, IL10, and IL23R–IL12RB2 are susceptibility loci for BD4, 5, and also revealed an interaction between HLA-B*51 and ERAP16 HLA-Bw4-80I, present on HLA-B*51 and HLA-A*26, is an additional BD susceptibility marker7. The gene discussed is IL23R; the disease is Behcet disease.