Ethics statement

The brown Hanwoo DNA was extracted either from AI bull semen straws or from blood samples obtained from different veterinary practitioners in the Hanwoo Improvement Center of the National Agricultural Cooperative Federation with the permission of the owners. The protocol was approved by the Committee on the Ethics of Animal Experiments of the National Institute of Animal Science (Permit Number: 2013–028). No ethics statement was required for the collection of DNA samples from the Brindle, Jeju Black Hanwoo, or Chinese Yanbian cattle because they were not sampled specifically for this study.