Overall, 23.5 to 28.0% of eRMS, osteosarcoma and GBM tumors exhibited LOH in at least one gene of the HLA class I pathway (HLA-A, -B, -C, TAP1, TAP2 and/or B2M), and 25.9 to 43.8% of osteosarcoma, Ewing sarcoma, NRSTS, LGG and HGG (non-GBM) tumors exhibited LOH in at least one gene of the HLA class II pathway (HLA-DRB1, -DQA1, -DQB1, -DPA1, -DPB1 and/or CIITA). The gene discussed is HLA-A; the disease is osteosarcoma.