We analysed transcripts relevant to DNA repair (Parp1), MAPK signalling (Braf, Mapk1, Rasgrp2) and cell cycle progression (Ccnt2, Ccnk, Cdk5, E2f1, Cdc45) and Vps16. In all cases, transcripts from AML cells with a recombined Rnpc3 locus exhibited elevated minor intron retention compared to cells in which the Rnpc3 locus remained intact (Fig. 4D). This evidence concerns the gene E2F1 and acute myeloid leukemia.