A material which is used to verify the performance of an assay intended to be used to evaluate a clinical specimen to diagnose or predict donor and recipient tissue compatibility based on one or multiple genetic markers from the major histocompatibility complex (MHC) family of genes. Genetic markers may include HLA-A, HLA-B, HLA-C, DRB1, DRB3, DRB4, DRB5, DQB1, DPB1, MICA and/or C4.