Behçet’s Disease as a Canker Sore: MHC-I-Opathy Versus Behcet’s Spectrum Disorders

Behçet’s disease is a chronic multisystemic inflammatory disorder characterized by recurrent oral ulcers and a close association with HLA-B*51. This review summarizes the clinical and genetic features of Behçet’s disease and compares susceptibility genes with those of other HLA class I-associated and stomatitis-related diseases.

In Behçet’s disease, recently identified non-HLA susceptibility genes are involved in the innate and acquired immune functions. An epistatic interaction between HLA-B*51 and ERAP1 is considered to play a pathogenic role in the disease. Similar findings have been also shown in other HLA class I-associated diseases, leading to a new concept of MHC-I-opathy.

Immune-related non-HLA susceptibility genes are shared among Behçet’s disease, recurrent aphthous stomatitis, and periodic fever aphthous stomatitis and adenitis syndrome, leading to another novel concept of Behçet’s spectrum disorders.

Recent genetic studies have shown that Behçet’s disease has both features of MHC-I-opathy and Behçet’s spectrum disorders.