1. Department of Molecular Biology and Functional Genomics, Stockholm University, SE-106 91 Stockholm, Sweden
2. Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
3. Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
4. School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand