In the fullness of time many of the theories and research tools relevant to autism that have been created by Prof. Simon Baron-Cohen and team from the University of Cambridge have not turned out to be nearly as wonderful as the media hype has suggested. Plenty of studies have failed to find evidence supportive of Baron-Cohen's ideas about psychological sex differences. The Reading the Mind in the Eyes Test has been used in many scientific studies, but during it's use the test's limitations have come to light. Even though Baron-Cohen's writing suggests that disability in reading facial expressions and face recognition are important elements of the autistic phenotype, researchers in these areas continue to discover autistic study subjects who have no disability in these areas. The Autism Spectrum Quotient (AQ), created in 2001 by Baron-Cohen and his team has been widely used for amateur self-diagnosis of Asperger syndrome, but a recent study has found that "The AQ-20 was only a weak predictor of ADOS-4 cases.", while there was found to be moderate agreement between clinical consensus diagnoses and ADOS-4 (Autism Diagnostic Observation Schedule module-4).
The assortative mating theory of autism is another brainchild of the professor. I believe this theory explains the apparent rise in autism spectrum condition diagnosis rates as the result of a combination of semi-autistic men and women who carry autism genes being more able in recent years to find gainful employment due to there being more technological jobs available that suit our autistic technical talents, along with the rise of the computer age, and these men and women carrying autism genes are supposedly now more able to meet each other and marry and breed together due to the concentration of geeky types in geographical concentrations of technological industries in places like "Silicon Valley".
If one breaks this down, there are supposedly two different effects happening - one is that autistics are theorized to be more able to have kids in the last few decades due to changes in the profile of employment options allowing the previously unemployable to find gainful work. I find this idea completely unconvincing, but I recognize that only a social science researcher could authoritatively say whether or not this idea is true. Technology has always been important to humankind, and I can cite many technological occupations which our family's female and male ancestors worked in. Engineering is not a new profession, and many of the housework chores, jobs and small business enterprises that women once did were technological in nature, so I don't believe that there is anything new about techies being able to make a buck.
Baron-Cohen also cites the scientifically accepted and quite long-established assortative mating effect as a factor behind the rise of autism diagnosis rates. Assortative mating is simply the tendency of similar people to marry. It apparently has been observed in many personality traits and mental health-related characteristics. Birds of a feather flock together. Assortative mating alone should in no way alter the rate of any disorder or mental feature in the population, as there are still the same absolute numbers of people marrying and having kids, regardless of who they settle down with. Assortative mating could only be relevant to increasing the rate of conditions if the conditions are the result of a recessive genetic inheritance pattern or something like this pattern in which two different genes which individually give rise to a similar trait or traits are by chance both inherited by one person, and the effects of both genes combine to produce a person with full autism or some other condition in full effect. To clarify, a recessive inheritance pattern is a pattern in which a gene "for" some condition is harmless or has no obvious effect in people who have ("carry") only one copy of the gene, but if a person has two copies of the gene an effect, which can be a bad effect, occurs in the person with two copies, presumably because the extra effect of a higher "dose" of the gene takes the individual over some biological threshold into a different or harmful state. So, for assortative mating to be important to the rate of autism in the population, autism would have to be inherited in a recessive pattern or something similar. So is it?
Remarkably little progress has been made in understanding the inheritance of autism, considering the huge amounts of money that have been spent to this end. This is because it appears that there are in fact many very different genotypes that can give rise to one supposedly unitary autism phenotype (the behavioural manifestation of autism). Instead of researching one genetic model of autism(s), researchers need to pursue many different models, and it appears that by far most of them do not operate in a classic recessive pattern. One model is in a dominant pattern, some types of autism result from single-gene mutations, some from chromosomal disorders, and epigenetic and imprinting models have been proposed. Some cases of autism are the result of spontaneous copy number variation mutations that arose only in that individual and weren't inherited from either parent. The word "recessive" does not appear even once in the Wikipedia's lengthy article about "heritability of autism". As far as I know, there is no recessive gene model of autism. I can see no good reason whatsoever why Baron-Cohen should assume that autism is inherited via a recessive pattern or something similar, and therefore I can't see how the assortative mating effect could be a significant or main genetic cause of elevated rates of autism diagnosis.
This isn't the only major problem with Baron-Cohen's assortative mating theory of autism. Many people would argue that there is no reason in the first place to feel a need to construct a theory to explain the rise in autism diagnosis rates, as it is only an error of measurement, and not a genuine raise in rates. Many professionals have argued that the only thing that has changed are diagnostic definitions of autism and related conditions, and changes in the motivations for parents to seek professional assessments for their children.
As if this all isn't enough reason to dismiss Baron-Cohen's theory as laughable, in a recent article about Baron-Cohen in Time magazine, a researcher who has actually done research into the assortative mating effect as it relates to the broader autistic phenotype, psychiatrist John Constantino, has reportedly stated that Baron-Cohen's theory doesn't explain the rise in autism diagnosis because "strong systemizers" as couples "....weren't having autistic kids at anywhere near the rate that would begin to account for the real rise we've seen in autism." (p.34 article by Warner in Time). I question the use of the word "real" in that article quote.
So, I would argue that the assortative mating theory of autism is just one more seriously misleading and invalid theory that Baron-Cohen has inflicted into the world-wide popular and scientific discourses about autism. A number of different types of harm might be done with this theory. The theory gives a false legitimacy to the false idea that autism rates are really rising, thus denying the reality of much of the social and personal history of autism and autistic families, which stretches back for many generations, and the idea of a modern surge in autism also adds fuel to the fire of fear that autism might be caused by modern environmental factors such as vaccinations, pollution, the internet or too much red cordial. Another type of harm caused by the professor's theory is the clear implication that some people shouldn't marry each other and some people shouldn't marry at all. I have no issue with individuals practicing eugenics in their own private lives, but there are many obvious dangers associated with eugenics as an issue of public policy imposed by institutions or experts upon individuals.
Another harm potentially caused by Baron-Cohen's brain-fart is the association in the popular mind of autism with the much-misunderstood concept of the "recessive gene". I'm not sure why, but many people have the idea that "recessive" genes are particularly sneaky, sinister things. The folklore is that these genes lie dormant in families but occasionally without warning they jump out of their hiding places to cause devastating rare genetic diseases. This is a bunch of crap, of course. Recessive genes associated with the more common recessive genetic diseases such as cystic fibrosis or sickle-cell anemia do not cause disease in most of the people who have the gene, and the fact that these genes are widespread is an indication that these genes may have useful effects when one only is inherited (homozygote advantage), but try to tell that to anyone over thirty who wagged science in high school. Maybe the word "recessive" reminds people of inbred aristocrats with receding jaws, or something.
How many more silly, evidence-free theories from this celebrity academic are we going to have foist upon us? Why has this guy been taken so seriously for so long by the media and academia? What is wrong with the way that science is practiced in the 21st century?
Autism's Lone Wolf
by Judith Warner
Monday, Aug. 29, 2011
Validating two survey methods for identifying cases of autism spectrum disorder among adults in the community
T.S. McManusa, J. Smitha, F. J. Scotta, H. Meltzera, S. Purdona, T. Berneya, D. Tantama, J. Robinsona, J. Radleya and J. Bankarta
Published online: 29 July 2011