Chromosone test to rule out diagnoses??

[monica2]

Just wondered if anyone elses paed has asked for this, it was suggested a few years ago at time of ASD diagnosis, tbh forgot all about it until recently, does anyone know what other things they would be testing for? Is it anything to be concerned about or is it standard??

I thought dd had a firm dx of AS though Monica?
I have to say haven't heard of anyone your dd's age having these kinds of tests, usually done about 2/3. Did they say what they were looking for?

Message withdrawn

I analyse chromosomes for a living - 'karyotyping' (looking at all of the chromosomes to check for small segments missing or duplicated) is a standard test for patients with ASD. It is highly unlikely that anything will be found, but there are some very rare chromosomal abnormalities that result in ASD features.

(Retts is now tested for by DNA testing RnB)

Thanks bluebear that's reassuring,
the test was to rule out diagnosEs BH ie. a dual diagnosis/something else on top of her diagnosis of Asperger Syndrome and it was suggested in our final report confirming this, at the time I assumed it was for medical research or something.

Do you think it is necessary to have the blood test bluebear?

And you RnB when are you free to see that new film???

Oh I see Monica. Hope it all goes okay and sorry I couldn't offer any useful advice xxx

I don't honestly think it would be for research purposes, monica2, I think it would be in the hope that it might help you. I wouldn't have thought it was necessary in that sense, it would just be to help you know the chances of further children having the same thing and so on. I would do what you think best, don't be railroaded if you don't want to. Incidentally, I didn't think Rett could ever be tested by karyotyping could it? It's caused by point mutations and tiny deletions that wouldn't have been spotted at the chromosomal level.

Message withdrawn

My girls were tested foe fragile x but nothing else.

Onlyjoking - really? I asked for dd to be tested and they said to me only boys could have it!

Some children with ASD have Landau Kleffner (sp?) syndrome. Don't know how you test for that. I thought Fragile X could be girls or boys.

Hi Monica2

Our ds has just been chromosome tested- he was diagnosed with global development delay and the paediatrician wanted to look at his chromosomes to see if there was anything there. The results showed that he has a duplicated piece of chromosome on his third set of chromosomes, and the paed is pretty sure that this is the reason for his delay, especially as me and dh were tested and we had nothing similar on ours.

Our doctor told us they do this just to ensure they have a full medical picture and in our case, as gdd is difficult to diagnose, they wanted to see if there was anything in my son's chromosomes to explain it. I think that it is done now so that every avenue can be explored to help a diagnosis.

Sorry if this is completely unrelated, but hope it sort of helps!

DD was tested for Fragile X and Down's Syndrome. She also had several other tests looking for metabolic disorders and several EEGs looking for syndromes associated with epilepsy.

My DD3 who has dyspraxia has part of her number 18 chromaosome missing. Her diagnosis is actually 18pdeletion syndrome with dyspraxia tendancies. i was also tested and found to have the same.

Hi again Monica - As you can see from the posters who have children with chromosome abnormalities - it is often helpful to have karytyping - it won't 'change' the diagnosis but if there is an abnormality present it can help explain the features and maybe give you an idea of how your child will develop (it depends on how rare the abnormality is) - if an abnormality was found it could also mean that you and your partner could be tested for carrier status so you would have a good idea of the risk of having another baby with the same abnormality.

RnB - don't think I've ever seen a reference looking at things that way round ie. number of AS kids with chromosome abnormality. I will have a look around for a reference.

Tamum - Rett's used to be referred for karyotyping out of desperation more than accuracy - before the locus was identified. (And following on from TC's thread - which I didn't want to re-open - I don't have a good reference for gonadal mosaicism - the clinical staff tend to offer a 0.1% risk from what i can see - which still seems high to me )

Fragile X - Girl's are usually referred to as 'carriers' but a proportion of them show mild features - much much milder than the boys. It's also a specialist DNA test now which is more accurate than the older chromosome test.

Clareren and Mumeeee - do you know about unique (www.rarechromo.org/) (can't do links with this keyboard) - it's a support group for families with rare chromosome disorders.

Hi Bluebear

Thank you for that link- I didn't know about Unique, but will definitely follow it up as there as so few resources for global development delay.

Thank you for taking the time to reply.

Davros when I asked the paed. to check dd for it he said the X was for male chromosone

Blossomhill, as bluebear says, Fragile X only manifests itself fully in boys, but can cause symptoms in girls. Your paed sounds rather ill-informed.

Thanks for that bluebear, I understand about the desperation, that would make sense. I have found various gonadal mosaicism estimates, but nothing very concrete, probably not surprisingly. I keep wondering if I know you, or at least know people in common....

It's a small community - so probably we know people in common - but I don't think I know you.
I'm diagnostic molecular cytogenetics at a children's hospital London.

Message withdrawn