Xue Wan1,2, Linyan Li1,3, Zulin Liu1, Zhenhai Fan1,3, Limei Yu4,5. 1. Key Laboratory of Cell Engineering in Guizhou Province, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003, Guizhou, China. 2. The Engineering Research Center of Zunyi Precision Medical Detection and Birth Defects Prevention and Control, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003, Guizhou, China. 3. Guizhou Provincial Sub-center for Prenatal Diagnosis, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003, Guizhou, China. 4. Key Laboratory of Cell Engineering in Guizhou Province, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003, Guizhou, China. ylm720@sina.com. 5. Guizhou Provincial Sub-center for Prenatal Diagnosis, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003, Guizhou, China. ylm720@sina.com.