An interesting article from the
Daily Torygraph. There's one on the Beeb as well, but shorter.
Parents' marriage choice may lead to autism
By Roger Highfield, Science Editor
(Filed: 30/01/2006)
The recent rise in autism may have been driven by the tendency of like-minded engineers, physicists, mathematicians and other "systemizers" to marry each other, according to a Cambridge University professor.
Around one child in every 100 - mostly males - has autism and the number of cases seems to be on the increase, though some argue that it is due to greater awareness and changes in diagnosis.
In a new study, Prof Simon Baron-Cohen believes the impaired ability of people with autism to communicate, recognise emotions and socialise is linked with the same genes that enable a person to systemize - find the laws that govern how a system works.
This is more often a male trait and present among scientists.
He has uncovered clues that suggest that when systemizers marry they have a higher risk of having children with autism. And he believes that systemizers are also more attracted to each other than one would expect by chance, due to what he calls "assortative mating".
Systemizers feel more comfortable in the company of each other rather than that of what he calls empathizers. "We have found clues in a range of studies we have conducted since 1997 that assortative mating is going on."
In the journal Archives of Diseases of Childhood this month, Prof Baron-Cohen reports various suggestive clues to link systemizing with autism.
According to a survey of 1,000 members of the National Autistic Society, fathers and grandfathers of children with autistic spectrum conditions are twice as likely to work in a systemizing profession such as engineering.
Students in the natural sciences have a higher number of relatives with autism than do students in the humanities, and mathematicians have a higher rate of autistic spectrum conditions compared with the general population.
The theory that both parents of children with autism are strong systemizers is also evident from a study that shows both mothers and fathers score above average on a questionnaire that measures autistic traits.
The parents are also faster at "visual search tasks" - in effect they have an unusually sharp eye for detail, just as their child with autism does - compared with the parents of unaffected children.
Brain scan studies of mothers and fathers of children with autism have shown that the mothers have a masculinised pattern of brain activity, again suggesting they are strong systemizers.
When all the evidence is taken together it suggests a genetic cause of autism, with both parents contributing genes that ultimately relate to a similar kind of mind: one with an affinity for thinking systematically.
Prof Baron-Cohen says the rise in autism could be driven because assortative mating is becoming easier: recent years have seen a rise in mobility, an increase in the employment prospects of systemizers - notably in the computer industry - and a rise in the numbers of women studying mathematics, engineering and other systemizing subjects at university, where they are more likely to come into contact with systemizing men.
He points out that the parents of children with autism may not have strong skills in such subjects, but that does not mean they are not strong systemizers.
The parents may for example have a remarkable memory for the names of songs in their CD collection, or for dates or telephone numbers.
He thinks the key characteristic is "exactness" in their style of thinking.
In the spectrum of conditions that count as autism, the largest groups are classic autism and Asperger syndrome. Both share features: a difficulty in developing social relationships, a difficulty in communication, the presence of unusually strong, narrow interests, and a strong adherence to routines.
They differ in that in classic autism, the person might have an IQ at any point on the scale, even in the learning disabled range, and the person invariably had a language delay as a toddler.
In Asperger syndrome, the person is always at least average in IQ, and may be well above average, and talked on time as a toddler.
Some months ago I wondered on SLAM if someone I knew had Aspergers, I guess this answers it. It also figures that his father is a scientist.
I had a roommate last month whom I suspect has Asperger's/autism
1. He has an inability to leave out detail: I once asked him where he got a small souvenir. He could have answered in 2 words: 'Heidelberg, Germany', but he went on a round-about manner, answering at tangents. It eventually took him 2 hours before he finished his answer, and the next day he emailed me the website of the shop which sold him the souvenir. When asked a question, he tends to give memory dumps of everything he knows and anything vaguely related.
2. He is extremely obsessive with his work and interests. He would work non-stop when in the mood, and work all day and night without rest and only junk food for sustenance.
3. In certain matters, he is an extreme stickler for detail...he ALWAYS wears the same type of outfit no matter what the weather. I even suspect he sleeps in that outfit. He once also told me, 'I get VERY angry and frustrated whenever people leave out prepositions in sentences'.
4. He ignores things outside his immediate sphere of attention if it isn't a life-and-death situation. There is a stack of junkmail just inside his apartment door because he just picks up his real mail, and doesn't see the necessity of picking up the junkmail.
Does this sound like Asperger's or autism?
Those of you attentive enough might realise who this roommate is, but for reasons of privacy, please do not mention his name here. PM me if you would like confirmation of your guess.
