1. Biomedical Research Center, Northwest Minzu University, Lanzhou, China
2. Department of Genetics, Inner Mongolia Maternal and Child Care Hospital, Hohhot, China
3. Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands
4. State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Gansu, China