Abstract: Preimplantation genetic screening (PGS) is a method used in the process of IVF-ET to help those patients with the high risks of genetic diseases to select a normal embryo to transfer by cell biopsy and genetic analysis, so as to get healthy babies. However, PGS is an invasive method at present which depends on the cell biopsy, with the potential risks for the embryonic development and offspring, and obstetrics and neonate. In recent years, the cell-free DNA with embryonic genetic material in the embryo culture medium has been found, which is positively associated with the embryonic fragment rate. This cell-free DNA has been tried to use in the detection of aneuploidy and single gene disease, which provided a new method of a non-invasive PGS with some advantages of non-invasive test, easy to get samples and the ability of embryo genetic detection at the molecular level. This technology needs to be furtherly optimized before its application in clinical practice because the cell-free DNA is easy to pollute, and the specificity is not good at present.
【Keywords】  

Key words: Preimplantation diagnosis, Prenatal diagnosis, Reproductive techniques, assisted, DNA, Cell free DNA, Noninvasive chromosome screening