HLA-B81 (B81) is an HLA–B serotype. The serotype identifies the HLA-B*8101 and B*8102 (very rare) gene products. B81 is more common in Subsaharan Africa. While there is a B81 serotype, serotyping of B81 is poor when simultaneously tested with anti-B7 or B48 antibodies. (For terminology help see: HLA-serotype tutorial)