Ten cases of nonsense mutations or frameshift deletions resulted in premature stop codons in HLA-DPB1 and cathepsin L (medulloblastoma), calnexin and legumain (HGG), HSPA8 (Ewing sarcoma), and CREB1 (NRSTS), and in splice site variants in HLA-DOA and cathepsin L (medulloblastoma), PDIA3 (osteosarcoma), and CD8B (HGG). The gene discussed is HLA-DOA; the disease is osteosarcoma.