Mutually exclusive and co-occurring mutations in brain cancer. (A) Distribution of mutations in ATRX, IDH1, TP53, EGFR, and PTEN across 283 lower grade glioma (LGG) and 288 glioblastoma multiform (GBM) patients. Each column is a patient. Red: mutated; white: not mutated. (B) Co-occurrence (orange) and mutual exclusion (blue) patterns suggest that genetic aberrations can target two distinct axes: ATRX/IDH1/TP53 and EGFR/PTEN. LGG and GBM samples with more than 110 and 164 mutated genes, respectively, were excluded from the analysis (cutoffs derived from mutation burden distribution, detailed in the Methods section).