Downs Syndrome - test?

[Pancha67]

Hello ladies, my partner has a brother and uncle with Down's syndrome. We have done some research into the genetic element of Down's syndrome.

There are two types, the by chance where there is an extra 21st chromosome (this happens in the cell forming process or where there is a parent that has a slightly altered 21st making them a carier - this has a chance of being passes onto a child causing an error in the 21st chromosome. Both types chances are increased by age.

The next options are to risk that my partner is a carier (likelihood is lots of people could carry lots of altered genes that do not pass along) or have the genetics of brother with DS tested but this is likely to cause great upset to the paternal family.

Thoughts please?

 

[Kess]

I suppose my question would be what would you do with the results? Would it put you off having children? Or would you "risk" it?

 

[Caite]

I agree with Kess that it would depend on what you would do with the result. You could speak to your GP (or equivalent if you're not in the UK) and be referred for genetic counselling. Even if you decide not to be tested, they would be the best people to inform you of the chances of your OH being a carrier.

The other option would be to wait until you are pregnant and then be tested. There are numerous non-invasive tests which pose absolutely no risk to the baby. What you have will depend where you are, but it will either be blood tests, which are done about 16-20 weeks, or nuchal test, where you have an ultrasound and blood tests, which is done around 12 weeks, so at your normal dating scan. These are not diagnostic, but will give you a risk factor for that baby having Down's Syndrome. It could be as little as 1:100,000 or as high as 1:2.

If your screening comes back as high risk (above about 1:150 or 1:100) you will be offered diagnostic testing, either an amniocentesis or chorionic villus sampling. Both methods carry about a 1-1.5% risk of a miscarriage but give a definite answer either way whether the baby has Down's Syndrome or not. But, with the risk of miscarriage, it's probably worth considering what you would do with the result before having the procedure.

 

[Pancha67]

Thank you that explained it very well

 

[Caite]

You're welcome.