Or maybe not. Not yet, anyway.
I have to admit, though, when I first read the headlines telling us that doctors at University College London Hospital had successfully implanted an embryo known to be free of the BRCA gene mutation, my heart skipped a beat. After all, as breast cancer survivors, how many times have we thought, “I’d give anything for my daughter (or son, for that matter) not to go through what I’ve gone through.” How we’ve wished we could spare them the horrors of breast cancer.
So what’s going on? Can genetic testing before birth really prevent breast cancer?
The short answer is no, not yet. But promising results have been achieved using a genetic screening technique known as pre-implantation genetic diagnosis, or PGD for short. Genetic pre-screening is performed during the in-vitro fertilization (IVF) process. Once an egg has been fertilized, a cell is taken from the embryo and examined for genetic disorders prior to the embryo being implanted in the uterus.
Originally, infertile couples looked to in-vitro fertilization as a way to have a child of their own, and often genetic pre-screening was done as a matter of course. As far back as 1990, PGD was used to avoid having children with cystic fibrosis, and is now also used to detect such disorders as Down syndrome, Hemophilia A and Tay-Sachs disease. Recently, genetic pre-screening has been able to successfully test for both the BRCA-1 and BRCA-2 genetic mutations, and this is why we are hearing about it in relation to breast cancer.
The fact that PGD can confirm there is no BRCA gene mutation in the embryo is enormous. But still, there is no guarantee that this child will not get breast cancer. As many experts have pointed out, and specifically Dr. Marisa Weiss, founder and president of Breastcancer.org, the majority of breast cancer is attributable to genetic changes later in life, rather than to an inherited genetic abnormality. In other words, the majority of us get breast cancer because of something that happens to our genes after we are born – not because of the genes we were born with. So, while the risk of breast cancer is certainly reduced when PGD confirms there is no BRCA mutation, the risk of breast cancer is not removed altogether.
Now, with the advances in PGD, many couples who are not infertile will be considering in-vitro fertilization and genetic pre-screening as a means to ensure a “healthy” child; i.e. a child free from specific genetic disorders. Critics fear this testing will open the door for the creation of “designer babies” – genetically engineered for health, beauty, intelligence and the like.
While designer babies in the truest sense may only be a product of our overactive imaginations, genetic pre-screening has the potential to open a Pandora’s box of social, political, and religious issues that will be difficult to transcend.
I can’t help but think of the adage, “Be careful what you wish for, lest it come true."