Childhood Autism and Assortative Mating (2012) [pdf]
economics.uchicago.edu
economics.uchicago.edu
The head doctor of an Autism centre told me there was a strong correlation between autism and genetics. I mentioned my wife (and her father) were almost certainly autistic but never diagnosed. This was confirmed as very common: one side or both usually have a history.
My wife and I met at University, doing the same degree. She was had a very logical and analytical mind, which is what attracted me to her.
We have an autistic child with a very strong aptitude for language conventions and solid mathematical reasoning (although the real strength is in language which is very common in Aspergers - a now defunct classification that I believe added value in understanding and finding like-minded children who were compatible socially).
My wife and I do not look alike, nor are we from a common ethnic background, unless you consider different parts of Western Europe to be sufficiently common genetics.
Anecdotally: I have spoken with quite a few Aspergers mums and dads. Most dads are in engineering or mathematics based jobs. Most of the mums I can recall are logical and have good analytical skills (employment status varies for mums). When I've met parents of Autistic children that were not Aspergers, I did not find a consistency of logical thinking. However, this could be my own selection bias. I've tried not to have bias, but I can't discount it.
Every person is on the spectrum. There are significant variations in the group defined as Autistic. It would be interesting to know if this group in the statistics were higher functioning (HFA) and to compare the results from HFA vs non-HFA.
What I found interesting is that teachers assumed my child had learning difficulties until we booked a formal assessment (classification: gifted or near gifted). My father in law was overlooked in a similar way and paid the penalty (at least, career wise).
I also am an engineer and the son of an engineer. My wife is a pharmacist and highly educated. We also dated in high school.
I know that within my paternal family there is a long history of high intellect and lack of social skills.
It's curious to me how much can be attributed to parents with higher education and means being more proactive to get a diagnosis for a high functional child versus the same demographic just being predisposed to ASD offspring.
It is a fascinating anecdotal connection, but it seems to be quite common.
My wife and I are both Dutch/Friesian, but I am reasonably certain we are not related. I am a programmer (with dyslexia), my wife is an artist. Both our fathers are technical with degrees/jobs in electronics. Her father has numerous patents in aerospace. My wife's mother has manic depression. Most of my cousins are dyslexic, one is autistic, a few have Aspergers children as well.
I think I've created the perfect storm to have a child in the autism spectrum.
I have very similar observation. For this specific scenario, I think we need to look up the whole family history, more than the children's biological parents. An ASD child's siblings could be neurotypical, which is the case for most families with ASD children that I have met. I wonder if a parent who is neurotypical but has siblings of ASD may have higher probability to have ASD children than those in whose family history there are no ASD members at all.
8 year boy on the spectrum. I'm tech. Wife is doctor. In a traditional school, boy has challenges (also is diagnosed with ADHD). Had him test, very high IQ. Super into science (outer space, oceans, physics etc) and has almost encyclopedic knowledge of those topics. In a STEAM based school, is super engaged.
We both suspect that wife's father is on the spectrum. Both wife and I exhibit traits but probably wouldn't qualify as being ASD.
Wife and I met in high school. Ethnically we are nothing alike (I'm northern European, she's a mix of African and eastern European).
We have two younger kids who appear NT at this point.
My son, though he's yet to have a conclusive diagnosis, is very likely on the autism spectrum, as he's a bright kid but is absolutely "unable to deal with systems that do not have a lawful structure".
What's interesting is that my wife and I did the complete opposite of assertive mating. We're from the same hometown, with completely different backgrounds. We had different friends, have different educational levels, different ethnicities, different heights, different looks, different interests, and different perspectives. Genuinely two people from "opposite sides of the tracks" who meet just from randomly being in the same building. But the attraction and chemistry were instant and enduring.
(We also, interestingly, both have extremely high adaptability, almost to a fault. It's been a learning experience to create the type of routine our son expects.)
I know: it's just one data point. But I've watched the rising rates of autism with great personal perspective, and it's certainly a complex and multi-deminsional issue.
The other things to iterate are that autism certainly is a spectrum full of individual variation (almost to the point of not being a useful label), and autism isn't necessarily a detriment—it's a perspective and mode of being. If we could systematically avoid autism through a deeper understanding of the cause, I'm wondering what the unintended consequences would be. I know one thing: I would never change my son.
Spellchecker strikes again?
> (almost to the point of not being a useful label)
Likely didn't help that now Aspergers is lumped in with the label, though the reason it was not there for the longest time was that people lacked some of the classic markers (language development in particular).
As for rising rates, i have a pin on the world turning more "social". Where before you could always retreat to a back room job or such, now a days most of those jobs are automated away. What is left is those that involve some amount of social interaction, thats far from a functional environment when dealing with autism.
Also makes the (dubious?) claim that marginal increased cost of caring for an autistic child is less than marginal likelihood for increased combined salary.
Moral of the story: make babies outside of your own ethnic group.
More off-topic, I find it creepy when I meet couples who look like each other and have a string of identical children.
I bet you already knew this is what I meant and didn't actually need me to spell it out for you. As an aside, I read elsewhere that you and your wife are both from Western Europe. That's actually a lot closer than I had in mind; I said breed with someone who really doesn't look like you. :)
I'm [genuinely] curious: do you find it creepy only for similar-appearing couples in your own race/ethnic group? Assuming you're not Japanese, for example, would you have that reaction to the sight of such a Japanese family?
This is not meant as a pejorative. My guess is that such a bias is probably common _within_ a race/ethnicity, but much less so when viewing couples/families of other races.
No, you should not: http://www.sciencedaily.com/releases/2008/02/080207140855.ht...
For example, for women born between 1800 and 1824, those with a mate related at the level of a third cousin had an average of 4.04 children and 9.17 grandchildren, while those related to their mates as eighth cousins or more distantly had 3.34 children and 7.31 grandchildren. For women born in the period 1925-1949 with mates related at the degree of third cousins, the average number of children and grandchildren were 3.27 and 6.64, compared to 2.45 and 4.86 for those with mates who were eighth cousins or more distantly related.
The autism rates in the Iceland are not that high, being 1.2% (Korea has twice as much autists as Iceland with their 2.6%): http://leftbrainrightbrain.co.uk/2013/07/05/autism-prevalenc...
I don't feel like that's necessarily a strong argument even if you don't think the world is going to have population problems, but if you do, that would be a pretty strong negative
If you marry to not have a child, or your priorities structured rather differently, my argument is null.
That is absolutely the wrong conclusion to make from the source. The suggestion of the source is that if two people prone to systemized-thinking mate (regardless of ethnicity), then the likelihood of autism is higher.
Your conclusion only makes sense if you believe certain ethnicities are more systemized than others. Thus, if you are from a systemized ethnicity, you should seek to mate outside your race. I don't think that is your intent. My inference is that your intent was to take this research and form some moral lesson out of it that fits your world view, or a world view that is fashionable.
I'm not so sure... I recall reading that there's a link between autism and parents of mixed ethnic background (sorry, don't have time to look up evidence right now).
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Diagnosed rates of autism spectrum disorders have grown tremendously over the last few decades. I find that assortative mating may have meaningfully contributed to the rise. I develop a general model of genes and assortative mating which shows that small changes in sorting could have large impacts on the extremes of genetic distributions. I apply my theory to autism, which I model as the extreme right tail of a genetic formal thinking ability distribution (systemizing). Using large sample data from the Centers for Disease Control and Prevention, I find strong support for theories that autism is connected to systemizing. My mating model shows that increases in the returns to systemizing, particularly for women, can contribute significantly to rising autism rates. I provide evidence that mating on systemizing has actually shifted, and conclude with a rough calculation suggesting that despite the increase in autism, increased sorting on systemizing has been socially beneficial.
[...]
if you marry your high school sweetheart, you picked among those people who happened to be born in your town, but if you marry your college sweetheart, you have picked among people who chose the same college that you did. More recently, the internet has made it easier to find people with similar interests or traits
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one less understood impact of assortative mating is the strong effect it has on the extremes of distributions. Positive assortative mating on a trait increases the variance of that trait, and the increase in variance causes large relative growth at the extremes of the distribution.
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the growing returns to mathematical ability may have contributed significantly to the increased prevalence of autism spectrum disorders. Diagnosed rates of autism spectrum disorders (ASDs) have grown tremendously over the last few decades, and a number of possible explanations have emerged. One of the more interesting possibilities is that ASDs are related to a genetic trait called systemizing, which governs how much our brains are wired for thinking about formal systems. High levels of systemizing may give ability in pursuits like mathematics and computer languages.
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So: increased prosperity and increased cultural literacy lead to increased assortative mating (and to later marriages) -- and thus, among those predisposed to autism, increased rates of autism... This is probably inevitable, more or less -- unfortunately...
This would be accurate, if people entered and exited high-school within an very short time window immediately following birth. This seems somewhat inaccurate as a model of actual reality, though.
Wouldn't marrying/reproducing in smaller circles historically have been higher throughout history as transportation and availability would have been less prevalent?
I would imagine that people tended to marry within their social circle at a much higher frequency in say the 1800s than they do now.
Also, it's always curious when I read studies about the increase in Autism rates. I am in the middle of reading Neurotribes and have read elsewhere that much of that increase can be explained in the broadening of the definition and increase in social awareness. Perhaps that doesn't account for the entirety of the increase, but I would be curious as to what percent we're attributing in this paper.
Thus the "odd fellow" out on that remote farm may well have fallen into what today goes for mild end Autism, or Aspergers, but functioned because the farm life was mostly self sufficient.
Sometimes i wonder how many of the old west mountain men were on the mild end, and opted for a life away from society.
My mother has been a home economics, and then a K-5 special education teacher in the same small school district for over 30 years. She's starting to get the grandchildren of some of her first students. She almost doesn't have to do the testing to label them, just look at who the parents and grandparents are. Looking at stories out of the Valley or Seattle about rates of high-functioning autism, and it starts to look like the first steps towards the Morlocks and the Eloi.
One of the more interesting Heinlein stories is Time Enough For Love[1], whose main character is part of an almost American Kennel Club-esque breeding program aimed at extending human lifespans through subsidizing assortative marriages.
People would scream eugenics and cry Nazi if anyone actually tried, but its interesting to think about what might happen if some insanely rich megabillionaire like Gates or Zuckerberg devoted their fortunes to a similar foundation, say, to get highly intelligent people to have more children and not wait into their mid 30s to start a family.
The author presents very thin evidence for his claim that the benefits of two "systematizing " mating outweighs the chance of them having and raising an autistic child.
It is an economics paper so the slant towards economics rather than biological is understandable. However, as the number of links on an individuals graph grows so too might the need for systematizing to make sense of it all.
All of these have increased in the last several generations:
1. Number of jobs in a lifetime and requisite number of skills needing to be learned and updated
2. Number of friends, coworkers and acquaintances that we are aware of and interact with.
3. Amount of information we have access too and are required to process
4. Number of options and alternatives in almost every area of our lives (except cable/internet providers of course)
> All of these have increased in the last several generations:
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> 4. Number of options and alternatives in almost every area of our lives (except cable/internet providers of course)
Actually, the number of options and alternatives in cable/internet providers has, over the last several generations, increased from 0 to a number greater than zero.
Not that this is an endorsement of the "transient, lawless, chaotic sexual desire will find a way" ethos of rock-and-roll, of course.