Chromosomal Microarray (CGH) testing-Is There Any Benefit??

We weighed the pros and cons of the microarray last spring when our son's cardiologist said that he thought our son had some "syndromic features". The cardiologist even went so far as to suggest "Williams Syndrome" - kiddo had the heart murmur, global delays, hypotonia, sensory processing issues, etc. My husband didn't want to do it - he thought it would be akin to opening "Pandora's Box", but I was adamant. I HAD to know - I figured knowledge is power.

It was probably the longest 10 weeks of my like - waiting for an appt at Children's Hosp, meeting the team, getting the blood draw, and then the wait for answers - good or bad. It turned out the kiddo is missing one chromosome on the Q-arm (23.6? or 26.3? I don't remember now) - which was "of no clinical significance". The geneticist said that most of us are probably missing one or more chromosomes here or there; what they are really looking for are missing sequences. I wept with relief. Our clinic at Seattle Children's also tests for Fragile X as a matter of course, and that test, not surprisingly to us, also came back negative.

If we could go back and do it again, I definitely would. But that's me - a good friend of mine asked, "Why? He's the same child you had yesterday, and he'll be the same child tomorrow. Knowing isn't going to change how you parent him, or how you love him." But I'd done what the cardiologist said not to do - rush home and look up Williams Syndrome online. In simple terms, it's similar to a "progressive Down Syndrome", by my description. I couldn't have that unknown hanging over my head for months and years. So the benefit to me was the peace of mind. If it had come back positive for Williams Syndrome or another syndrome, or if he had pre-cancer markers or anything else that could be revealed by the CGH, I would arm myself that information as I sought early answers/early treatments.

~ D.

Well, my son has delays and we had the fragile x testing done which came back negative. It is a simple blood test, so no big deal. We did not have the microarray testing done. I think it all depends on you. I was on a never ending search to figure out what was going on with my son, and even though the treatments would have been the same, I felt a diagnosis would have helped me feel like I knew what I was dealing with. My son never was diagnosed with anything other than SPD which is what I truly feel are his problems so I did not do any genetic testing. If you are fine with not having a diagnosis and the treatments will be the same, then no need to do the testing really.
It seems extreme to do a lot of testing due to only speech delays, so many kids out-grow that anyway, but whatever makes you feel the most comfortable!
Sorry, just went back and looked at your past questions, and you are the one who has a son just like mine! I have a slightly different login, due to not being able to sign in with my real e-mail, but have you ever looked into sensory processing disorder for your son. It is not a "real" diagnosis yet, but it explains soooo much for my son! They are trying to get it into the next DSM, which I really hope so insurance will pay for more stuff!!

I had the microray done on my son and the results were negitive. The drs wanted his done to see if there was any other explaination for his behavior. The downside to this test is its so new that it's not very well understood. Good luck

If it something your doctor recommended why wouldn’t you? The benefit it will give will be answers for your son’s issues. If there are any. Just because you wouldn’t do anything different doesn’t mean it isn’t important to know what you are up against. My 2 year old daughter has several genetic issues and we went through it. She also is delayed. Yes it is scary and very stressing while you wait for the tests BUT we found out that she does have some genetic disorder we just don’t know what it is yet (there is no name for it)…so we have done more tests. She has a cardiologist, a genetics, and a urologist we see regularly to get answers. So far we have ruled out the obvious stuff such as downs’ and others alike. We have been going through this for over a year and a half. I just want answers. I want to know what we are dealing with and what is causing her delays. What will be scary is once the testing is done we may not have the answers and then we will just have to wait and see what happens. Good luck with your son. I hope you do the test so you can get answers and be able to help your son as appropriate.

Hi Luv,

In a report on the consensus statement made by the The International Standard Cytogenomic Array (ISCA) Consortium following two international workshops on this topic, Miller et al. discusses the value of chromosomal microarray testing vs. the older G-band karyotyping method in a 2010 article published in American Journal of Human Genetics. (BTW, this is usually abbreviated CMA in the literature -- are you thinking prehaps of chorionic gonadotrophin (CGH) by mistake?)

Quite simply, this method allows for testing for hundreds of potential genetic anomalies simultaneous. It is much faster and cost effective than other tests, and less labor intensive. Miller et al. conclude: "CMA offers a much higher diagnostic yield (15%-20%) for genetic testing of individuals with unexplained developmental delay/intellectual disability, autism-spectrum disorders, or multiple congenital anomalies than a G-banded karyotype (approximately 3%, excluding Down syndrome and other recognizable chromosomal syndromes), primarily because of its higher sensitivity for submicroscopic deletions and duplications. "

Frankly, it's kind of a shot-gun approach to trying to figure out what's going on, but can be very helpful. Results from this test, in conjunction with clinical history and physical examination, can better help your doctor figure out what's going on and the best course of treatment. It can help identify potential problems that might not evolve for another decade or two, and give you the ammunition to institute life-style practices that might help avoid such problems from ever developing, or at least mitigate their severity. I would say if it is being offered to you and you can afford it (or the insurance will pay for it), definitely get it done.

Best of luck with your son.

M.,
By any chance have you seen a DAN! doctor? Our son is dealing with speech delays as well and we discovered through some tests that he has bacterial and yeast issues. We have started treatment for those issues and we have noticed a GREAT improvement..no speech yet, but definitely more comprehension of speech and a greater vocabulary of signs.
We had the genetic testing done as well, but only as a formality with our neurologist. Since we have seen such huge improvement in the last few months with his treatments, we are convinced that our son's issues are not genetic but bacterial and yeast related.
Just to prove my point, our son had a developmental screening at 21 months and was cognitively tested at being 6-9 month equivalent. Three months later, he is now considered 36 months cognitively, and he is 24 months. Since 21 months he was treated for yeast and bacteria and has had 2 months of ABA therapy. That is all that has changed. Additionally, since doing these treatments he is better behaved and is sleeping better.
BTW: DAN! stands for Defeat Autism Now, but many children with speech delays struggle with the bacterial issues. Whether your child is autistic or not, a DAN! doctor can help!!!