LYL1 and leukemia: In contrast to Sca1‐Lmo2 T‐ALL, Lmo2 was expressed in Sca1‐Lmo2 + nu/nu leukemia (Fig 4C) and expression array data showed enrichment in human early T‐cell precursor (ETP) ALL genes (Fig 4D), in agreement with human ETP ALL cases that commonly showed LMO2/LYL1 deregulation (Liu et al, 2017).