Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.|East Anglian Medical Genetics Centre, Cambridge University Hospitals, NHS Foundation Trust, Cambridge CB2 0QQ, UK.|National Institute of Agricultural Botany, Cambridge CB3 0LE, UK.|Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.|Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.|Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.