Genetic testing for family members

[User13355]

Hello,

We are TTC and just found out DH's sister has a genetic mutation (carrier) and her daughter has now been diagnosed with Cornelia de Lange syndrome (a rare genetic condition). I am wondering if my DH needs to be tested to see if he is also a carrier and where to begin with finding this out. Would it be via the GP?

We are currently waiting for results from trio (me, my partner and son) whole genome sequence testing. When my daughter found out she was pregnant we spoke to our genetic counsellor who requested a referral for my daughter.

It might be worth asking DH's sister to ask her genetic counsellor and they may suggest a referral needs doing.

When DD1 was diagnosed with a rare pathogenic gene variant (mutation), after genome sequencing, we were tested to see if we were both carriers. We were. They suggested her twin get tested as she had symptoms too. They also wrote a generic referral letter for anyone in the family on both sides, so they could give it to their GP to get a referral for genetic testing.

In our case, any of DD’s female cousins and her sister need to know before they get pregnant, because the condition is exacerbated by physical stress (such as pregnancy) and their obstetrician needs to know.

As pp says, ask the hospital which did the genome sequencing for a generic referral letter?

So it really depends on the genetic condition. For example, my son has Acrocallosal syndrome and myself and husband are both carriers. If my sister was also a carrier, her child would not be at risk unless her husband was also a carrier. So it really depends.
After a (very) quick Google, it looks like Cornelia de Lange syndrome is not inherited and it occurs randomly. I would do some research, the info is out there xx

@MummyB1990 I have spoken with the genetic counsellor who saw my DH's sister who confirmed our niece inherited Cornelia de Lange from her mother (my husbands sister) and that she has a 50% chance of passing the condition onto future children . However, their analysis of her DNA shows that my DH's sister did not inherit this from her parents but rather it first occurred spontaneously for her at conception. So there is no risk my DH is also a carrier.

Ah ok, well that sounds positive. However, if it's going to worry you your whole pregnancy, I would just both get a genetic panel done. Enquire with your GP, but they may have to refer you for private testing. We had absolutely no idea we were carriers and our first child was not affected, so being aware of it would have been much less stressful! Xxx