MLLT1 and neoplasm: The dysregulation of several HOX genes and the upregulation of MYC (MYC-C) in MLLT1-mutant FHWT provide indirect support for an altered interaction between PAFc and the SEC in MLLT1-mutant tumours, as these genes are all recognized to be regulated through transcriptional elongation via the SEC (refs 23, 39, 40, 41).