TP53 and glioma: Genomic testing revealed five alterations: H3F3A K27M, ATRX loss, TP53 (R282W), PTEN loss and CDK4 amplification but no mutations in PDGFRA, IDH1, or EGFR. Since 2016, WHO classifies this tumor type as Diffuse Midline Glioma, H3K27M mutant.