To mimic the effects of rearrangements at 3q26 in AML, we created a tetracycline (Tet)-inducible allele of Evi1 (termed Evi1TO) in the mouse by inserting seven Tet operons within the first exon (Fig. 1a15), allowing for the induction of all three isoforms of Evi18,9. The gene discussed is MECOM; the disease is acute myeloid leukemia.