The clustering of breaks in intron 7 of API2 and the consistent "in frame" API2-MLT fusions could therefore reflect certain functional constraints crucial for clonal outgrowth..     ///    Our data suggest that the API2-MLT fusion might result from a non-homologous end joining event after multiple double-strand breaks.     ///    "Hitherto the chimeric API2-MLT transcripts are all ""in-frame"" and predominantly fuse exon 7 of API2 to different MLT exons. "