There are actually a bewildering array of microchanges to the genome that are associated with ASDs. The most common, occuring on the 16th chromosome, is found in around 1% of autistics surveyed. (And none of the NTs surveyed, which is why it's associated with ASDs.) However, depending on the research cited, the total number of microchanges that may be part of the spectrum is up to 15 or so.
Last figure I heard on probability was that if at least one parent is on the spectrum, there's a 20-30% chance that any children will be, as well. I would imagine that increases if both parents are spectrumites (to coin a word).
Anecdotally, I believe my father may have had Asperger's, and I'm pretty sure of one maternal uncle, as well. There was also at least one cousin who was a Kanner's autistic. (Remember, you young'uns, that back in the day, an autistic relative was hidden out of sight, regarded as shameful. And Asperger's didn't even exist as an official diagnosis until about thirteen years ago!) I am AS, my younger sister is autistic. My daughter is autistic; one nephew has been diagnosed with AS and ADHD (a wonderful combination!). There are probably others scattered about, but until recent years, it was hard to get an AS diagnosis, even after it came into being; I still hold that most of the "epidemic" is probably related to changes in diagnostic standards since 1994. (I also think another part may have had to do with the "dot-com boom", when more geeks became potential mates, and thus had more little protogeek children...)
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.
10 Mar 2008, 3:32 pm
