1. Medical College, Guizhou University, Guiyang, China
2. Department of laboratory medicine, Guangzhou Second Provincial General Hospotal, Guangzhou, China
3. Discipline Inspection and Supervision Office, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
4. Prenatal Diagnostic Center, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China