IDH2 and astrocytoma (excluding glioblastoma): Consistent with YMG25R parent tumor cells, gain of PDGFRA and amplification of CDK4 and MDM2 were observed, while CDKN2A HD was identified in the xenografts, qualifying for astrocytoma, IDH-mutant, CNS WHO grade 4 according to the WHO CNS5 criteria (Fig. 4E, Additional file 1: Fig. S4B).