MrXxx wrote:
oliverthered wrote:
I've had a bit of a poke around and
'Autism' is a bit of a dumping ground in a way, for a collection of 'symptoms' and not causes.
The reason for this is quite simple. No causes have ever been firmly identified. All that exists for causes are speculations, none of which have ever been confirmed.
oliverthered wrote:
Some of those causes [I say as scientificly as possible] relate to some forms of retardation, and I know that some forms of retardation can result in physical traits and appearance traits such as those mentioned in the start of the tread.
Some of this may be purely down to muscle tone, caused by lack of control or otherwise due to cognitive 'defects'
Downs syndrome for instance has some particular traits which I believe go Beyond muscle tone.
I have a big head, and the ambionic? fluid was tested before I was born to see if I had Type I diabetes. (I believe that that condition can affect growth hormones and such).
So under the broad umbrella of the autistic spectrum, there is most probably some physical characteristics dependant of the cause of the autistic traits. It should imagine that it's also possible that the causes can develop into something other than Autistic spectrum traits but with the same physical characteristics.
The cause for Downs Syndrome was firmly identified decades ago. The cause is genetic. Extra genetic material in the 21st chromosome is the cause, which can be detected with genetic testing before and after birth.
While the cause for Autism is suspected to be genetic as well, no suspected chromosome has ever been linked to it in any statistically significant way. It is suspected by many scientists now that Autism may be genetically caused by any of several different genetic abnormalities. There may be several different chromosomes responsible, and it may take one of many different combinations of abnormalities to cause Autism.
Downs Syndrome results in similar physical traits among those who have it because only a single chromosome abnormality needs to be present to cause it. That same single chromosome problem causes the similarity in everyone with Downs Syndrome. Autism, on the other hand, if it is caused by genetics, is strongly suspected to be a much more complicated combination of possible genetic abnormalities, which if this is true, aren't very likely to cause similar physical traits across everyone on the spectrum.
There may very well be groups and subgroups that share the same genetic abnormalities, as well has similar physical traits among each group or subgroup. No specific groups of genes have ever been identified that cause Autism though, and no one has ever found physical traits that can be reliably proven to be "Autistic," or that can be shown to be shared by everyone with Autism.
Actually while there's no single genetic cause of autism, there are genetic conditions (that don't necessarily have to result in MR, even Down's syndrome doesn't always) where a larger percentage than usual are autistic. Down's syndrome, Fragile X, CdLS, and Noonan's, are ones I've heard of. (One of those, can't remember which, has 60% of people with it are autistic.) One study also found that about 40% of autistic people they studied had such a syndrome that hadn't been identified until the study. Many of these syndromes have mosaic forms or milder forms or both, that can make them harder to identify, and not all of them have one specific gene discovered that accounts for all of them. But they do have higher than usual autism rates. I've also heard that there are some minor physical traits that are more common in autistic people, but not universal by any means and often traits that taken on their own would blend into the general population or even be seen as especially attractive-looking (and because of scientific bias, 'attractive looking' 'dysmorphic' features aren't looked into as much as 'unattractive looking' ones). So yes there's plenty of appearances that are sometimes linked to autism, just not always.
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"In my world it's a place of patterns and feel. In my world it's a haven for what is real. It's my world, nobody can steal it, but people like me, we live in the shadows." -Donna Williams
26 Oct 2010, 3:38 pm
at 21 you'd think I'd be insulted but I find the whole thing to be pretty funny b/c people usually think I'm older. Also I'm clumsy, one night I got excited about auditions for "American Idol" coming to my state when the phone rang so I ran to pick it up and was going to the kitchen to talk when I got caught on my pantleg and fell into the utility closet door where a plastic bag of soda cans were *facepalm* needless to say I had the bruise for two weeks!
