1. Université Paris Cité , CNRS, Epigenetics and Cell Fate, F-75013 Paris , France
2. Directors' research, European Molecular Biology Laboratory (EMBL) , Heidelberg , Germany
3. Epigenetics Programme, The Babraham Institute , Cambridge CB22 3AT, UK
4. Wellcome Trust – Medical Research Council Cambridge Stem Cell Institute, University of Cambridge , Cambridge CB2 1QR, UK
5. Collège de France , Paris , France