This work was supported by the Wellcome Trust [grant numbers WT062023]; the European Molecular Biology Laboratory (EMBL); the National Institutes of Health (NIH) National Human Genome Research Institute (NHGRI); the National Institutes of Health (NIH) National Institute of Allergy and Infectious Diseases (NIAID); the Biotechnology and Biological Sciences Research Council (BBSRC); the Medical Research Council (MRC); and the European Union. Funding for open access charge: The Wellcome Trust.
