1. European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK
2. Division of Biology and Biological Engineering 140-18, California Institute of Technology, Pasadena, CA 91125, USA
3. Informatics and Bio-computing Platform, Ontario Institute for Cancer Research, Toronto, ON M5G0A3, Canada
4. Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
5. Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA