MECOM (Ecotropic Viral Integration Site 1 (EVI1) and Myelodysplastic Syndrome 1 (MDS1-EVI1)

The human EVI1 gene spans approximately 65 kb of genomic DNA. 14 of its 16 exons are coding (Fig. 1A ). Transcription can initiate from alternative exons 1 a, b, 1c, 1d, or 3L (Fig. 1B), and several alternative sp lice variants of the EVI1 mRNA have been described (Delta324, -Rp9, Delta105; Fig. 1A). The human MDS1 gene consists of 4 exons spread over a genomic region of more than 500 kb. MDS1 exon 4 i s located less than 2 kb upstream of EVI1 exon1a. The MDS1-EVI1 mRNA presumably results from splicing of the second exon of MDS1 to the second exon of EVI1 (Fig. 1B).