Preimplantation what????

What is PGD/PGS?

PGD stands for Preimplantation Gyenetic Diagnosis…so diagnosing a problem with the genes in an embryo prior to implanting it in a woman’s uterus. PGS stands for Preimplantation Genetic Screening and is a little bit different. PGS is used to detect a more broad range of defects in an embryo. According to Genesis Genetics, the lab we will be using for our genetic testing, around 50% of all embryos contain some sort of genetic abnormality which will  lead to a miscarriage or birth defect. PGS is used to screen for these abnormalities. It is often used for women over a certain age or those who have had trouble conceiving in the past.

PGD is different in that it aims to pinpoint a specific gene mutation which a couple is trying to prevent. We will be using PGD to prevent our children from specifically inheriting epidermolysis bullosa. This will be a long process that we don't fully understand at this time. I'll explain the parts that we do know...

Step one: (Done!)  Perform a blood test to see if they can pinpoint the exact gene that is causing Brian’s condition. Without knowing which gene is defective, there is no way to know where to look for the mutation. Brian had this blood test completed last year and they were able to determine that KRT14 is the defective gene.

Step two: Create a “gene probe” – This part of the process is confusing for me. They will take blood samples from our immediate family to create a baseline for their diagnosis. I am assuming by immediate family they mean our parents. I am not sure what they will do for my father as he passed away when I was little. I guess we will find out.

Step three: Harvest eggs and create embryos. In order to get the eggs, I will need to go through infertility treatments. I will give myself a series of injections over about a months time to stimulate multiple follicles to release eggs; usually a woman’s ovaries release one egg per cycle. It has been described as your ovaries growing to the size of a bunch of grapes...which sounds less than pleasant. I am definitely not looking forward to that part. Once the eggs are ready, the doctor will go in with a GIGANTIC needle and get each of the eggs. (I have a bad habit of watching things like this online and freaking myself out about them. I have looked at that needle around 100 times and wanted to cry every time i saw it!) Once they have retrieved the eggs, they can then fertilize them and create embryos.

Step four: Once the embryos have had a chance to grow for a few days, a sample of cells will be taken from each one. These cells will be sent to the genetics lab on the east side of the state for testing. They will use the DNA Probe from step 2 and the blood test from step 1 to figure out which embryos will be healthy and which ones have the gene for EB.

Step 5: Implant the embryos and hopefully grow a healthy baby! :D

Obviously this is an extremely simplified description of an extremely detailed process. Genesis Genetics has recently released a short video explaining PGS/PGD. It focusses on PGS, but the process is pretty much the same. 

You can watch the video on PGS here!

While we have done a lot of research and our geneticist has given us some info, we still have a lot to learn. We have our initial consultation at The Fertility Center in a couple weeks. We are excited, nervous and hoping they can start us in the right direction. I will of course post an update with what we have learned after this appointment. 

- Emily