FLT3 and myelodysplastic syndrome: Morphologic examination of the bone marrow demonstrates erythrodysplasia in all Wt1+/R394W recipient mice, myeloid proliferation in the majority of the Flt3+/ITD recipient mice, and features of both MDS and MPN in the majority of the Flt3+/ITD/Wt1+/R394W recipient mice (Figure 5D).