This model mimics human myeloid malignancies bearing rearrangements at 3q26 for the following reasons: (1) the native, unmutated gene, with all of the alternatively spliced isoforms, is upregulated (Supplementary Figure 1H); (2) the levels of EVI1 expression are similar to activated MECOM alleles (Fig. 1b); (3) because we induce EVI1 in the transplanted setting, only hematopoietic cells overexpress EVI1; (4) the overexpressing cells are mixed in with normal cells, as is the case in incipient human myeloid malignancies. Here, MECOM is linked to myeloid neoplasm.