1. Medical Genetic Department, The Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, P.R. China
2. Department of Geriatric Medicine, The Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, P.R. China
3. Department of Neurology, The Eleventh Clinical Medical College of Qingdao University, Linyi People's Hospital, Linyi, Shandong 276000, P.R. China