17%囊胚期胚胎同時兼具正常與異常染色體

PGD顯示，17%囊胚期胚胎同時兼具正常與異常染色體
這些胚胎仍可能發展成正常胚胎

囊胚期胚胎PGD並非全然準確

Of more significance may be the 17% of blastocysts that contained both diploid and aneuploid cells. The fate of these embryos is unclear. It is possible that the aneuploid cells have a growth disadvantage or are eliminated by processes such as apoptosis, leading to a decline in their numbers as development progresses, ultimately resulting in a normal fetus. If this scenario is correct, some diploid–aneuploid mosaic blastocysts may be viable and might be incorrectly discarded if aneuploid cells were detected following TE biopsy. 

http://humrep.oxfordjournals.org/content/26/2/480.full