DUX4 and leukemia: To investigate whether and how TCF12 facilitated IGH::DUX4‐mediated transcription, the abnormal transcriptional activation of IGH::DUX4 targeted genes such as AGAP1, CLEC12A, ERGalt, CLEC12Aalt and C6orf89alt was measured by qRT‐PCR in leukaemia cell lines REH and NALM‐6.