LMO2 and acute lymphoblastic leukemia: However, in order to prove that, for T‐ALL development, LMO2 expression does not need to be maintained beyond the initial step of reprogramming, one would require an experimental system capable of limiting the expression of LMO2 to the target cell‐of‐origin compartment, since otherwise it would be impossible to discard a function for LMO2 in posterior tumor development, as exemplified by the Rosa26‐Lmo2 + Sca1‐Cre model.