In the World Health Organization (WHO) classification of AML and related neoplasms, inversion or translocation of chromosome 3 at the MECOM locus [inv3(3;3)(q21q26)/inv,(3) t(3;3)(q21;q26.2)/t(3;3)] have been recognized as recurrent genetic abnormalities45 (Fig. 3). This evidence concerns the gene MECOM and acute myeloid leukemia.