Embryo Screening

This is taken from a discussion I took part in concerning preimplantation genetic diagnosis, a very touchy subject from an ethical point of view, and also from a technical point of view:

“…. There have been many issues with genetic testing of the embryos for hereditary diseases such as Huntington Disease for many reasons. First, of course, during pregnancy women can have a genetic test performed on the fetus in order to find out if their infants will be affected by a known disease or not. However, many centers refuse to perform this test as it divulges information about the parents as well and usually leads to pregnancy termination. The test in itself cannot predict the time of onset of course. However, more interestingly in my opinion, this opens the door to a whole new approach to birth, in vitro fertilization with pre-implantation genetic diagnosis (PGD). This procedure is also known as embryo screening and it allows couples at risk of transmitting a genetic disease to ensure their descendants to be unaffected by the genetic disorder through artificially combining many sperm cells from a man with many egg cells from a woman to create many embryos. Then, cell samples are taken from all of the embryos and the DNA analyzed for the defective genes. The non-disease carrier embryos are selected and artificially implanted into the mother’s uterus. This allows the parent to ensure a “disease free” child and avoid having to go through the painful termination process, in case the pre-natal test is positive (see below link to video for Comprehensive Chromosome Screening technic, a novel approach to embryo screening). This method, while very appealing, is an ethical nightmare, as it opens the door to the quest for a “perfect baby” …”

Y.S.H.

  

References:

  • Embryo Screening and the Ethics of Human Genetic Engineering, By: Leslie A. Pray, Ph.D. © 2008 Nature Education
  • [Ethics and medical genetics], Lacombe D., J Int Bioethique. 2012 Jun;23(2):95-102, 178-9. French.
  • Preimplantation genetic screening: “established” and ready for prime time?, Gleicher N, Weghofer A, Barad D.,Fertil Steril. 2008 Apr;89(4):780-8. Epub 2008 Mar 18. Review.