ASD and risks in younger siblings:/genetics , advice please!

[Ruby1985]

Hello all, I am a mother to a six year old who has high functioning autism and I have a two year old son. Until now the two year old seems to be NT and I can see huge differences between him and his brother at this age but I'm still very aware and monitoring all the time if he could have ASD too.

I have just found out I am pregnant I do not know what to do and really would like opinions advice about autism and genes. Am I more likely to have other kids with autism? What are the chances? When my eldest was diagnosed I was told about a blood test but from what I understood does not rule out if any future kids would have autism is this correct? So could my second be NT but third might not or vice versa?

Sorry for the waffle hope I've made some sense!!!

it really depends. we had genetic testing for DC1 and she has an exceedingly rare chromosome deletion which is the underlying cause. DH and I were tested for the deletion too and we don't carry it. Genetics told us that we therefore don't have an increased risk of having another child with ASD. But I wouldn't have known had we not had microarray testing.

When my eldest was diagnosed I was told about a blood test but from what I understood does not rule out if any future kids would have autism is this correct?

I guess the blood test was for microarray testing (genetics). Did you get it done?

Genetic testing can identify underlying chromosome issues. If sometjing is found then usually the parents are tested too to see if they carry the genes. This gives you a much better idea as to how likely another child with ASD is.

Thank you for all your replies. Coffee the way the doctor explained it and the autism health visitor was that it would not show how likely I am to have another child with ASD but more like my results and others would be put into a pool of research for future research on links on genetics and ASD that's what I gathered lol!

Do u guys advise microarray testing? I did not plan a number three as well so would defo like to know the chances etc if this test shows such a thing!

We have the same situation - DD1 microarray testing has a genetic deletion but DH and I do not have the same. Therefore DD1 sibilings at no increased risk for the same/ASD.

We would never have known about the genetic issue if I had not asked for testing after her ASD diagnosis. We had some reasons for doing so but were initiallly dismissed by the doctors for suggesting it and told nothing would show up. He ate his words when he called me some weeks later with the results! Knowing her genetics result does however give us so much more information to work with and it also help us and her in the future should she ever have children of her own as she will have a 50:50 risk to pass this on to them. She has choices later on if she wants them.

OP, without microarray you get statistics which may or may not bear any resemblance to your personal risk.

however, microarray testing takes ages to come back (we waited 6 month and were considerdd fast) and wont help with with this pregnancy.

I don't think it's possible to give a general statistical likelihood of having more than one child with ASD.

We have one child with ASD and two without, and absolutely no family history so our odds for ds2 were probably close to zero. Or at least the same as the 'general population'.

Other families have a clear genetic link and their odds are probably extremely high. I know someone with 4 children with ASD but there is a very strong family history.

Thank you for your replies, this has clarified many points I was unsure about and the way it was explained to me