Friday, 6 April 2012

Preimplantation Genetic Diagnosis

Biology Blog

Ever wondered if there was a method available that allows you to hand pick your own child? A recent article by Connie Karambela and Eddy Rivera discusses the idea of the ‘total designer baby’.

(CartoonStock, n.d.)

So what is fuelling discussion for a ‘designer baby’? A process called Preimplantation Genetic Diagnosis (PGD). Dr Meike Uhler, an infertility specialist, who works for the Fertility Center of Illinois gives an accurate definition of the PGD process. He states, “PGD is specifically the area within vitro fertilization where we can look for a particular disease and not transfer back embryos with that disease.” (Karambelas, C & Rivera, E 2010)

The PGD Process (Barlow-Stewart, K & Mona, S 2007)

The first PGD birth occurred many years ago with scientists determining the gender of an embryo, which had produced through IVF.  (Handyside, A.H 2011) After this breakthrough discovery was made the parents then decided which embryo they would like to use for the pregnancy. This decision was usually based using the recommendation of a medical practitioner as to which embryo would be most viable and have the highest chance of surviving throughout the pregnancy.

This gender selection process was quite simple as it only involved determining whether there was an XY or XX chromosomal combination to determine the sex. Nonetheless this was a great accomplishment as it allowed couples who had XX chromosome genetic conditions to be gender selective and choose an embryo with an XY combination.

Although PGD is providing many newborns with a healthy and genetic disorder free life there are worries that the process is not ethical. Many activists, both social and religious, believe that IVF and PGD is a form of murder when some embryos are terminated. The other ethical around is that the process of PGD is sealing the child’s fate before they have any choice. Arthur Caplan is the Bioethics director at the University of Pennsylvania believes that “it gets controversial when you’re going to use the technique just to try and have a child with traits that you want.” (Karambelas, C & Rivera, E 2010)

The field of PGD has now expanded into being able to test for any genetic condition that a family has a history of being affected by. The accuracy of testing has increased dramatically with the Preimplantation Genetics Diagnosis International Society (PGDIS) releasing figures that the diagnosis for inherited diseases has a 99.5% accuracy rate. (Kuliev, A & Martin, R 2010)  Also PGD has offered a greater chance of success through the pregnancy. A comparison of pregnancies with PGD and pregnancies without can be seen in the figure below.


 (Reproductive Genetics Institute n.d.)

The term ‘designer babies’ is a very misleading and provocative as neither doctors nor scientists us it. The process of PGD is not one that manipulates parts of an embryo that provides children with their unique characteristics.

PGD is certainly not at the stage where a baby could be ‘designed’. It is merely an accurate method that can be used to diagnose and minimise the risk of a child being born with a debilitating genetic condition.  In the future after much more research and exploration who knows what is possible. Although something that is known for sure is that any process that involves genetic enhancement, manipulation or genetic screening will always be heavily scrutinised to make sure the tests are ethical.


CartoonStock n.d., Designer Baby cartoon 6 - search ID rjo0403, viewed 18 March 2012, <>.

Barlow-Stewart, K & Mona, S 2007, PREIMPLANTATION GENETIC DIAGNOSIS, Centre for Genetics Education, viewed 18 March 2012, <>.

Handyside, A.H 2011, ’Preimplantation genetic diagnosis’, Obstetrics, Gynaecology & Reproductive Medicine, vol. 21, no. 3, pp. 68-79, viewed 17 March 2012, <> .  

Karambelas, C & Rivera, E 2010, Custom delivery? Technology is getting closer to the total designer baby, viewed 15 March 2011, <>.

Kuliev, A & Martin, R 2010, Current Progress in PGD and Future PGDIS Activities, Preimplantation Genetics Diagnosis International Society, N/A, viewed 17 March 2012, <>.

Silber, S.J n.d., WHAT IS PRE-IMPLANTATION GENETIC DIAGNOSIS (PGD)?, The Infertility Centre of Saint Louis, viewed 18 March 2012, <>.

Reproductive Genetics Institute n.d., Aneuploidy, viewed 18 March 2012, <>.

1 comment:

  1. Preimplantation genetic diagnosis, or PGD, is a procedure that may be performed along with in vitro fertilization or other assisted reproductive technologies to identify genetic defects in embryos that are created with the procedure. PGD may be used if one or both of the parents have a known genetic abnormality, as the embryos are put through a panel of tests looking for various common chromosome abnormalities.

    PGD Preimplantation Genetic Diagnosis