Representation of the cooperation of oncogenic events. The major subclasses of T-ALL are shown based on the expression of the transcription factors TAL1, TLX1, TLX3, HOXA genes, NKX2-1, or LMO2/LYL1. For each subclass, additional genes are shown that are most frequently mutated in that subclass. The PRC2 complex contains EZH2, SUZ12, and EED.