C1 tumours were enriched for RB1 mutations or SVs (P = 3 × 10−5), as well as frequent SVs that affected ATRX (P = 6 × 10−14), but not DAXX. RB1 and ATRX mutations were largely mutually exclusive (Extended Data Fig. 13b). The gene discussed is ATRX; the disease is neoplasm.