Microdeletion 15q11.2

[JMomma]

My 24 month old son was recently diagnosis with a microdeletion at 15q11.2. I haven't found a whole lot of anything useful, or other people with the same diagnosis. I don't know if this deletion means something at all (the genetist said they will know more in a year or two). I know AS/PW encompass his deletion and more, so I decided to ask here if anyone has ideas.

My son is 24 months, 19 lbs, 31 and 5/8 inches. Which makes him really small. He has always been low tone, but only slightly and his tone has increased. He sat at 6 months, rolled over at 12 months, and a week later started to crawl, he was walking at 20 months. He still has problems with uneven surfaces and stairs (and other gross motor skills). His balance/vestibular skills are not so great (and it is becoming more obvious the older he is getting). He is highly verbal (as in regularly uses 2 word sentences, sometimes 3-4 words, is starting to use pronouns and different tenses). He doesn't show any signs of cognitive delays either. He did have a pericardial effusion in utero, and did have bilateral pulmonary artery stensis (which resolved), and a very small PFO (which is getting smaller, his cardiologist discharged him at a year, it is so small, it has never even been heard). His anterior fontenel is still open. If it weren't for his size, we would have most likely not done anything special/worried too much about his gross motor delays. But he really is excessively small (as in his older brother was the size he is now at 10 months old).

Any thoughts? I'm trying not to stress/worry too much, but my kid's problems just don't make sense. In general, he really is a healthy, strong willed little boy.

[Magster's Mom]

That's really fascinating. I think the next step would be a methylated analysis so you know which chromosome has the deletion.

If the deletion is on the maternal chromosome, then the next question is whether the UBE3A gene has been deleted. It doesn't sound like it since if the UBE3A gene was deleted, your son would have Angelman, and he doesn't have the symptoms.

If the deletion is on the paternal chromosome, then the next question is whether the SNRPN gene is deleted. If the SNRPN gene is deleted, then your son would have Prader-Willi. That also doesn't sound very likely since your son has unusually good muscle tone and development for a child with PWS.

It could be that your son has a tiny deletion that is so small that neither the SNRPN gene or UBE3A gene has been deleted. It would still, however, be useful to know which chromosome contributed the deletion. There are other imprinted genes in this deletion area that likely contribute to some of the symptoms of either AS or PWS. In both disorders, children who have inherited both their 15 chromosomes from one parent are "higher-functioning" and less affected than children who have deletions. This is likely because there are other genes in this region of the 15th chromosome that contribute to develoment. If your son has a tiny deletion, he could be missing some of these other genes, but not have either AS or PWS because he has THOSE genes.

The important thing is that it appears your son does not have either AS or PWS. There is a 3rd syndrome that affects this portion of the 15th chromosome, called Idic15. It doesn't sound like your son has any of those symptoms either. But if you check out the website for IDEAS, you might find it interesting to read about the genes that are of the most interest in IDIC 15. http://www.idic15.org/genes-of-interest.html You also might contact IDEAS and register with them.

Depending on where you live, it might be good to get in touch with a geneticist who carefully studies the 15q region. One of these experts is presenting at the CASS conference in Montreal this month. A scientist who has dedicated their life to understanding the function of the genes in this region of the 15th chromosome is going to be your best bet to help you understand if this deletion is going to be significant or not. I'd be happy to help you find a researcher.

Erin
_________________
Erin Sheldon, mom to Maggie, del+, DOB 8/14/03 and Ella DOB 8/19/06. www.sheldonhickey.com

See Maggie star in her movies on YouTube: http://ca.youtube.com/user/magstsersmum

[JMomma]

Thank you for the link. The genes that are deleted for my son are TUBGCP5, CYFIP1, NIPA2, and NIPA1. Which I think they are thinking have more to do with behavior disturbances. I'm not sure how much more testing we are going to be doing. At this point, I don't think there are a whole lot of "answers" out there for his deletion, regardless if it is on the maternal or paternal chromosome. The genetic clinic that he is seen at is fairly large and well known and known to be a "leader". As the genetic doctor he see says, my son "almost looks like he has a syndrome". Almost being a key word. His head is in the 75% for his age, but his height and weight are below the bottom of the charts. His face is proportionately small to his head, and his hands are proportionately small as well. Many, many syndromes and other causes are eliminated because my son is so verbal and at this point appears to be cognitively normal as well. (As in one of his recent doctor appointments, he was sitting on the floor taking apart a Teck Deck (a tiny skateboard that can fit in your hand) with a screwdriver to amuse himself, the doctor observed that just watching him do that knocks out a whole range of things). Yet other parts of him have made more than one doctor say "Interesting. I wonder why he is like that." Me too.

[mmadeline]

Hi, I don't have time to write properly, but please check the Unique - Rare Chromosome site, as I believe there are some relevant microdeletions registered with them. http://www.rarechromo.org/html/karyotypes.asp?ch=15q+Microdeletion
_________________
DS 4 (GDD Del-, Methylation-, mutation+). Walking since turned 3. Can speak one word, can sign about 5 to 10 words.
DD 2 (GDD, FTT, mutation+). Learning to take steps with walker. No verbal communication.

[SFMom]

Hello
I read your message and was somewhat relieved. This is because I have been trying to find some information about it but just am not able to find anything. There is very little information available on this deletion. It is not yet identified as syndrome. I am scared at this point and quite worried that there is so little information. Both me and my husband got tested and we found that my husband carries the same deletion. My husband is highly educated and very bright. He is tall, a scientist and an athlete. It is as though this deletion has not touched him. I hope we will be able to communicate more.
-RM

[johnark]

After I read this article I got cunfused.

I thought deletion 15q11.2 is angelman syndrome. Did I get wrong information? My son's blood test result said there's deletion in 15q11.2 and doctor confirmed he has angelman syndrome. The report doesn't state Micro deletion. It states just "deletion in 15q11.2. does this makes some difference? Is it different microdeletion and just'deletion'?

My son(15 months now) is still crawling(comando crawl) but can't sit by himself, can't pull up, doesn't make any sound(like words) but makes meaningless sounds. eating seems ok but he never show satisfaction when to stop eat. He just eat continously if I don't stop. His weight is way under the percentage chart (I think he's under 3%) but his hight & head is about 10-20% (not sure exactly). He doesn't immitate but he know mom & dad and strangers now.

Thanks for reading!
_________________
Jeeyoon

Patrick (Del +) - 4/1/2009
diagnosed 4/26/2010

[SFMom]

Well this is what we have been told by a lot of doctor. In case of Angelman there are lots of genes missing. In has of 15q11.2 there are 4 genes missing. We have been told it is not Angelman or PWS. It is in the same region but not the same thing. I am 17 weeks pregnant and desparate to seek more information.

[SFMom]

Dear JMomma

I am very interested in getting in touch with you. Could you please write to me at eco_richa@yahoo.com.
Regards
-RM

[SFMom]