English: The human leukocyte antigen B (HLA-B) gene is a member of the major histocompatibility complex (MHC), a region of the human genome located on chromosome 6. The MHC (also known as the human leukocyte antigen (HLA) complex) includes three subregions, designated as class I, class II and class III. Each of these subregions contains a variety of genes that mainly code for proteins involved in the immune system. HLA-B is part of the class I group, along with HLA-A and HLA-C, all three of which code for their eponymous proteins [Article:15573121]. Class II genes include HLA-DR, HLA-DP and HLA-DQ [Article:22076556], and class III genes include complement components and cytokines such as complement factor B (CFB) and members of the tumor necrosis factor (TNF) family