Ash1l, Ctnnb1, Hoxa7, and Hoxa9 were also upregulated in the single mutant Mir-142−/− GMPs compared to WT, but the key co-factors Meis1 and Pbx3 were not, potentially explaining why these mice failed to develop leukemia (Supplementary data file 1). Here, PBX3 is linked to leukemia.