After publication of the original article , the authors noticed a typesetting error in the hyper-linking of the additional files. The additional files have been relinked and can be accessed via the original article. Author details 1 Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland. 2 Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA. 3 Qualitas AG, 6300 Zug, Switzerland. 4 Dogs Global, 6871 EK Renkum, The Netherlands.