MandM hope you dont mind, but I copied and pasted your post into a new thread because I felt it was really informative and might not get the `airing' it deserves under the MMR thread.
Hope I've not been too presumptuous :-
Anyhow, here's what MandM has to say:-
Haven't been able to log on since Thursday and was just catching up with some of the postings. I noticed that Charlie95 and OnlyJoking had both asked a few questions about Williams Syndrome and just thought that you might like to know a little bit more about it as it is quite rare and most people don't seem to have heard of it - I certainly hadn't until 3 years ago!!!!
Williams is a genetic disorder that only occurs in about one in every 20,000 births and can occur without any family history of the disorder, although people with Williams Syndrome have a 50%+ chance of passing it on if they have children of their own. There is also no link between siblings, so if we were to have another baby (dh says 'if', I say 'when'!)it would be at no more risk of having Williams than any other baby.
The actual cause of Williams is a missing elastin gene from Chromosome #7 - there should be two and babies born with Williams Syndrome only have one. This is detected via what is known as the FISH test.
As with some other genetic disorders, people with Williams Syndrome inherit certain distinctive facial characteristics - gorgeous ones in my dd's case of course!
The syndrome also brings with it charcateristic behaviours and developmental delays in one/several/all areas - in other words as per everyone else children with Williams are complete individuals each with their own particular talents, special qualities and particular needs.
I've (hopefully) included a link to some further information at the bottom of this posting that you can click on to have a look at what I mean and find out more.
Apologies if this is long winded, just thought it would be useful/interesting to those of you that didn't know much about this disorder.
Also, are there any other Mumsnetters around with a child who has Williams Syndrome. If so, I would be really interested to hear from you.
[MandM did include a link here, but it didnt work]