MECOM and myeloid neoplasm: First, a number of alternatively spliced mRNAs are transcribed from this locus and one of these (EVI1) is overexpressed in myeloid malignancies with chromosome rearrangements, usually an inv(3)(q21q26) or t(3;3)(q21;q26) that reposition a GATA2 enhancer at 3q21 downstream of MECOM at 3q36 (ref. 23).