As expected from previous work, mice with Flt3ITD/+ alone developed MPN, while loss of one or both Dnmt3a alleles cooperates with the Flt3ITD mutation to elicit the development of an MPN or an acute leukemia of varying lineages including AML and T lymphoblastic leukemia /lymphoma (T-ALL) (Figure 2A). The gene discussed is DNMT3A; the disease is acute leukemia.