Post # 1
Two of my cousins, on my maternal side have had a child with down syndrome. They’re not sisters – one cousin is from my aunt (mom’s sister,) and the other cousin is from my uncle (mom’s brother).
We’ve never had down syndrome in our family previously… but both of these have happened within the past 12 years.
This makes me incredibly nervous about having a child.
Both of my cousins were in their late 20’s when they had their children. My older cousin got tested, and apparently it was a false-negative. My other cousin never got tested.
I’m 28, and thinking about starting to TTC soon. I know this sounds terrible, but I’m just being honest. I have no where else to ask these questions, or express these feelings: I couldn’t handle having a child with down syndrome.
Is down syndrome hereditary?
Is there a DNA test that you and your SO can get to see the probability of down syndrome in your blood?
How accurate are the blood tests they do at 11-13 weeks?
Post # 3
My understanding is that while down’s syndrome is a genetic disorder (in that it’s an extra chromosome) it’s not hereditary. Nor is there anything blood borne that could predict your likelihood of having a child with down’s.
I just did my 13 week testing, and it’s followed up by another set at 15-20 weeks, and supposedly it takes both of them to get the full idea of your risk level, and even then a amnio would be required to get a more definitive diagnosis.
Post # 4
Yes, Down syndrome can on rare occasions be inherited though most cases are not hereditary.
Moasic Down syndrome cannot be inherited, translocation Down syndrome can. Essentially what happens is an unaffected person can carry a rearrangement of genetic material between chromosome 21 and another chromosome, called a balanced translocation because there is no extra material from chromosome 21. Despite not having signs of Down syndrome, people who carry this type of balanced translocation are at an increased risk of having children with the condition. This trait of carrying a balanced translocation between chromosome 21 and another chromosome is heritable. Only about 4% of Down syndrome cases are translocation DS. If the mother is the carrier, the risk of passing the translocation is between 15% and 20% and if it’s the father, the risk is about 3%. (Statistical sources from Mayo Clinic Down syndrome info page.)
You’re not a horrible person for not wanting to handle a child with Down syndrome and wanting to take precaution. You’re also looking out for a future child and the implications of if they were to be born with Down syndrome and what their quality of life would be like. It’s okay to have these concerns.
It’s recommended that if you have family members who have children with Down syndrome, you should consult a genetic counselor who can assess your risk of passing Down syndrome to your children. Among other things, a genetic counselor can take a blood sample and have it screened to find out if you carry it. They also help assess your odds of having it, passing it on, etc., based on who in your family also had it and passed it on. Prenatal screening for Down syndrome such as nuchal translucency ultrasound, amniocentesis, and chorionic villus sampling can also be discussed during a future pregnancy and risks vs. benefit weighed out so you can make the decision you feel best in your situation.
Good luck and I hope that helped, sorry it was so long lol. 🙂
Post # 5
@AquaGrey8962: I don’t think it sounds terrible, and I have a sister with downs.