If cellular identity is to be maintained, it is important that actively transcribed chromatin stretches remain in a loose configuration as long as these genes are needed. Marc Bühler and his group have uncovered a novel positive feedback loop – crucially involving the histone acetyltransferase Mst2 – which ensures that (transcriptionally active) euchromatin cannot be easily converted into (inactive) heterochromatin. Because some of the players in this feedback loop have been implicated in cancer, these findings are relevant to our understanding of human diseases.