1. Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.
2. Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA.
3. Harvard–MIT Division of Health Sciences and Technology, Boston, MA 02115, USA.
4. Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
5. Department of Computer Science, Volen Center for Complex Systems, Brandeis University, Waltham, MA 02454, USA.
6. Center for Molecular Medicine and Genetics and Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201, USA.
7. Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA.
8. Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
9. Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.