CD34 expression was low in NPM1::MLF1 and NPM1::CCDC28A cells compared to other mouse AML cells transformed by MLL::AF9 or SETBP1/ASXL1 mutations (which we refer to as cSAM cells), similar to that observed in NPM1c-driven AML (Supplementary Fig. 2C). Here, MLLT3 is linked to acute myeloid leukemia.