1Department of Molecular and Cellular Biology, Harvard University, Cambridge MA 02138, USA
3Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
4Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
5FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA
6Biozentrum, University of Basel, Switzerland
7Allen Discovery Center for Cell Lineage Tracing, University of Washington, Seattle, WA, USA
