The Silicon Valley Phenomenon
One way to test the assortative mating theory is to compare couples in which both individuals are strong systemizers with couples who include only one strong systemizer—or none. Two-systemizer couples may be more likely to have a child with autism. My colleagues and I created a Web site where parents can report what they studied in college, their occupations, and whether or not their children have autism (www.cambridgepsychology.com/graduateparents).
Meanwhile we are exploring the theory from other angles. If genes for technical aptitude are linked to genes for autism, then autism should be more common in places around the world where many systemizers live, work and marry—places such as Silicon Valley in California, which some people claim has autism rates 10 times higher than the average for the general population.
In Bangalore, the Silicon Valley of India, local clinicians have made similar observations. Alumni of the Massachusetts Institute of Technology have also reported rates of autism 10 times higher than average among their children. Unfortunately, no one has yet conducted detailed and systematic studies in Silicon Valley, Bangalore or M.I.T., so these accounts remain anecdotal.
My colleagues and I, however, have investigated the rates of autism in Eindhoven, the Silicon Valley of the Netherlands. Royal Philips Electronics has been a major employer in Eindhoven since 1891, and IBM has a branch in the city. Indeed, some 30 percent of jobs in Eindhoven are in the IT sector. Eindhoven is also home to Eindhoven University of Technology and High Tech Campus Eindhoven, the Dutch equivalent of M.I.T. We compared rates of autism in Eindhoven with rates of autism in two similarly sized cities in the Netherlands: Utrecht and Haarlem.
In 2010 we asked every school in all three cities to count how many children among their pupils had a formal diagnosis of autism. A total of 369 schools took part, providing information on about 62,505 children. We found that the rate of autism in Eindhoven was almost three times higher (229 per 10,000) than in Haarlem (84 per 10,000) or Utrecht (57 per 10,000).
Male Minds
In parallel with testing the link between autism and systemizing, we have been examining why autism appears to be so much more common among boys than among girls. In classic autism, the sex ratio is about four boys to every girl. In Asperger's, the sex ratio may be as high as nine boys for every girl.
Likewise, strong systemizing is much more common in men than in women. In childhood, boys on average show a stronger interest in mechanical systems (such as toy vehicles) and constructional systems (such as Lego). In adulthood, men are overrepresented in STEM subjects (science, technology, engineering and math) but not in people-centered sciences such as clinical psychology or medicine. We have been investigating whether high levels of the hormone testosterone in the fetus, long known to play a role in “masculinizing” the developing brain in animals, correlate with strong systemizing and more traits associated with autism. A human male fetus produces at least twice as much testosterone as a female fetus does.
To test these ideas, my colleague Bonnie Auyeung of the Cambridge Autism Research Center and I studied 235 pregnant women undergoing amniocentesis—a procedure in which a long needle samples the amniotic fluid surrounding a fetus. We found that the more testosterone surrounding a fetus in the womb, the stronger the children's later interest in systems, the better their attention to detail and the higher their number of traits associated with autism. Researchers in Cambridge, England, and Denmark are now collaborating to test whether children who eventually develop autism were exposed to elevated levels of testosterone in the womb.
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Add CommentSimon Baron-Cohen suggests that assortative mating between geeks "might spread autism genes". But surely the opposite is true. He may be right to claim that that when geeks mate with other geeks their children are more likely to be autistic. However, as he himself points out, autistic individuals have lower reproductive fitness. So, this must mean that geeks who mate with other geeks are likely to have fewer grandchildren -- fewer, that is, than if they had mated with non-geeks and had children who were not autistic. The net result must be that assortative mating, even if it works to increase the incidence of autism, actually works to reduce the spread of genes for autism.
Reply | Report Abuse | Link to thisDid I overlook it, or was any mention of other factors beyond genes absent from this article?
Reply | Report Abuse | Link to thisIf this were purely a genetic disease, then it would have been with us throughout history. Genes do not change that fast, so there must be an environmental trigger. Since the first cases started appearing at the same time as vaccination, and increased with more vaccinations required, parents should be forgiven for thinking there is a connection. Health authorities have not found any other causes, and we keep being bombarded with this genetic message, which cannot be the only factor. No wonder parents are having to figure this out by themselves and do not trust health authorities, and people like this author.
It is time for the medical establishment to grow up and stop pretending that medical issues are black and white. Yes vaccination has saved lives, but we don't know the full consequences of this much monkeying with the immune system. So, how about a moratorium on genetic articles about autism? Someone needs to do better research on the subject and help parents who don't know how to avoid having their child join a lost generation of ruined lives.
"..having their child join a lost generation of ruined lives."
Reply | Report Abuse | Link to thisI am annoyed at this comment and I am sure I am not the only one. There's all kinds of wrong in that quote.
I only read the preview, but isn't the whole point of the article about the genetic gifts that Autistic people have that contribute to the advancement of the scientific (if not the entire)world?
I am a parent of a scientifically minded autistic child who has one parent an engineer, one a mathematicion and 4 grandparents that are scientists/engineers/doctors. I know my child will lead a rich and fulfilling life following in his ancestors footsteps.
His life is nowhere near ruined and he may even discover something that will earn him a Nobel Prize.
I believe it's the attitude that being autistic = a ruined life that may prevent these kids from getting the support they need in school to excel in their gifts.
Autism can be linked to reproductive success in the same way as the genes for sickle cell anemia, i e having one copy of the gene might increase fitness while having two copies decrease fitness. That way a "harmful" may survive in the population.
Reply | Report Abuse | Link to thisSince all types of autism and now Asperger's Syndrome are all lumped together by a recent revision to the psychiatric diagnosis guidebook as "Autism Spectrum Disorders", it's increasingly difficult to discuss what are often quite disparate conditions. As I understand, those with high functioning autism and Asperger's Syndrome are very similar in their abilities to function (but with distinct limitations) in society. However, many if not most with autism suffer debilitating disabilities and may not be able to care for themselves much less function in society.
Reply | Report Abuse | Link to thisI wholeheartedly agree that many "ASD" sufferers can, perhaps with greater obstacles to encounter and overcome, not only function but prosper in society and enjoy a very satisfying life. Moreover, as the author points out, many are very significant contributors to the general benefit of society.
Perhaps these beneficial attributes are what perpetuate "ASD" genes in the general population. One can even argue that, in modern technological society, the ability to systematically analyze complex conditions is so highly valued and significantly beneficial that the frequency of associated genes should be expected to increase in the future...
"Since the first cases started appearing at the same time as vaccination, and increased with more vaccinations required, parents should be forgiven for thinking there is a connection."
Reply | Report Abuse | Link to thisPerhaps uninformed parents can be forgiven for perpetuating the myth fostered on the victims of a now discredited physician in the past, but they should also consider that, if autism is a developmental condition and that vaccinations are often scheduled to coincide with conditions like the child's loss of immunities initially endowed by their mother's immune system, the two events could each be coincidentally related only to child development. As always, correlation does not infer causation.
Tentative hypothesis that seems to fit with other findings re: rates of autism and aspergers in less-developed societies. Perhaps parents who are overly concerned about early academic development that are partly responsible. Their emphasis on reading and other intellectual activities inhibits the "natural" progression of development where the child learns about its physical environment and develops skills and self-confidence in it. Related, spending a lot of time with adults who are exerting subtle pressure for the child to learn what the adult wants may also interfere with social play with other children where other basic skills and self-confidence usually develop.
Reply | Report Abuse | Link to thisI realize these conditions are complex and other factors play a part. Just interested in what others may think.
Why are we always so eager to use genetics to explain our differences? The article summary here has no mention of environment. What readily comes to my mind is that engineers are migrant workers. Specialty education forces people to relocate to specialty jobs. Any autism researcher should know the well-established link between change in familial location and autism incidence (diet as culprit). Not mentioned here at all. It should be considered first. The questions should have been asked: How far apart are the locations where these engineers grew up and where the now live, vs the non-engineers?
Reply | Report Abuse | Link to thisKlinefelter Syndrom (KS) is associated with autism risk and along with Down's Syndrome is the most common genetic sydrome associated with increased autism risk. KS is not inherited and is always caused by an extra X chromosome. Half the cases are caused by an XY sperm mutation and half the cases are caused by an XX egg mutation producing the KS XXY genotype. Interestingly, in contrast to Baron-Cohen's high testestorone theory, Klinefelter Sydrome is associated with a drop in testosterone production in the neonatal testosterone surge period.
Reply | Report Abuse | Link to thishttp://ghr.nlm.nih.gov/condition/klinefelter-syndrome
McCAuliffe's group recently discovered exposure to increasing levels of PCB and DDT congeners, as measured in blood, produced increase frequency of XY sperm in sub-fertile men.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3339457/pdf/ehp.1104017.pdf
I'm not sure where you got the bizarre idea that Autism didn't exist before vaccinations but your idea is wrong. Autism existed centuries, if not thousands of years before vaccinations, it just wasn't a formal diagnosis until the advent of modern medical knowledge. Perhaps if you bothered to do any real research you would realize just how moronic your post sounds. The term "Tuberculosis" is a recent label that replaced "consumption". Names change but that doesn't mean the disorder is new. How many Autistics were called changelings, slow, possessed, or other archaic terms that meant "not like the rest of us"?
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Reply | Report Abuse | Link to thisI can say about my child that very early, maybe 6 months (I forget but his mother remembers very well) when I (the primary care giver) went off to work in the evening, his mother had a difficult time consoling him when he cried.
Interestingly though, she noticed when the shopping channel was on, or when CNN news was on (with subtitles), he would stop crying. He wouldn't stop crying when his mother held him and those channels weren't on but he was comforted when his mother held him with her back to the TV.
By age 3 he was reading in two languages and reflecting back, we see that even at the earliest age, he had more interest/understanding in letters than in his mother's and actually anyone's words/touch.
I am a teacher but honestly was quite surprised when I realized at two that he was teaching himself to read. OK there were words on the pictures we looked at such as "gorilla", but my style is to talk about the card. Big gorilla, black gorilla, I want a banana (act like the gorilla and pretend to eat a banana).
Also, I did point at the words when I read a book, but again I talk more about the pictures than I do reading. And the reading was only rhyming books, but he did not acquire intonation in English until after mastering his second language. It was really weird where he picked up verbal intonation in his second language (age 6) much more easily and then started to develop it in his first.
Actually, we ended up at those activities because his ability and interest in verbal language was late to develop and because I could just tell what he was interested in. I just naturally chose the things that held his attention. Still, it is really very true to say that any neurologically typical child would end up talking about the pictures like their parent was instead of learning to read the words.
There is no doubt whatsoever that my child was neurologically predisposed to seek out the patterns in symbols as opposed to paying attention as other kids do to facial expressions, and tone of voice.
Reading to this day remains intrinsically rewarding to him in a way that verbal discussion does not.
It's all making sense to me now. As an architect who's been plagued with the forced reality of "collabarating" with engineer's for decades, I always suspected something was inherently wrong with most of these individuals. I always knew that one part of their brain was not activating properly: the sensing, empathising, spiritual, moral parts of the brain. They seem to be stuck on the left side of their brains...systemitizing...a true Mr.Spock. But, being their moral superior, I KNOW that I must aspire to coexist with these strange beings, therefore I do and repeatedly forgive them their many moral lapses and unimaginable cruelties, as lesser evolved beings. I guess we still need human calculators after all.
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