Furthermore, GFP+ leukemia cells infiltrated into the spleen and liver (Fig. 5c,d), and double mutant (Mir142−/− + IDH2R140Q) recipients exhibited more severe splenomegaly compared to both the single mutant (WT + IDH2R140Q) recipients (Fig. 5e) and the Mir142 knockout alone (Fig. 3e). The gene discussed is MIR142; the disease is leukemia.