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Old 04-24-2011, 10:30 PM
gcochran gcochran is offline
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Join Date: Apr 2011
does not meet the standards...

Why would you reference an article in New York Magazine about the scientific merits of our Ashkenazi paper, when you could be quoting People or Tiger Beat?

The lady who wrote that article (Jennifer Senior) thought that it must not be a real scientific paper because we didn't use footnotes. I doubt if she had ever read a scientific paper in her life before covering ours.

We did have difficulty getting published. That is true. The process was interesting. For example, the editor vetting the paper at Quarterly Review of Biology thought that we had to be wrong when we said that very few Ashkenazi Jews had farmed during the Middle Ages - we (relying on histories and such) had said that they had mostly had white-collar jobs, with an increasing fraction of crafts and low-level retail in the last quarter of that period, due to an expanding population. I wondered where he had gotten the idea of medieval Jewish farmers - and guessed that he had developed his picture of Jewish history from watching Fiddler on the Roof. And he had: he confirmed it when I asked him. After I showed lots more documentation, he agreed that we were right on that point, and that the paper was reasonable - but of course they would never publish anything that controversial. Six months lost.

Sometimes the process was more efficient: we asked an editor who ran a journal on human evolution if she would be interested. She was, but called us back later, crying: the Dean of her department has said that he'd kill her journal and hinted at firing her if she published it. That took only a few days.

We convinced Takahata, at Genetics, that our genetic analysis made sense, and that the Ashkenazi genetic diseases were most likely a side-effect of selection rather than founder effect, particularly since they concentrated in a couple of enzyme paths. The most striking cluster of genetic diseases involved the build-up of sphingolipids that , when increased, cause more growth of dendrites, and longer axons with more branches... But he didn't want us to talk about what we thought had driven that selection - what trait had changed - even though his old friend and co-author Klein had reviewed the paper favorably and asked him to 'have the courage' to publish it. He didn't, so we went elsewhere.

There have some people interested in testing it. One Israeli evolutionary biologist
was quite excited: thought that they should throw the kitchen sink at the problem, bring a real team, with population geneticists and psychometricians and historians.
Look at the mutation carriers in the Israeli army and check against cognitive tests. But that didn't go anywhere: it turns out that hardly anyone in Israel wants to know this, although not for the reasons you might expect. You see, the explanation for increased intelligence only applies to the group that actually has it, the Ashkenazi Jews: it doesn't predict a similar effect in non-Ashkenazi Jews, who make up about half of the Jewish population in Israel - and who score about a standard deviation lower on IQ tests, are about three times less likely to finish college, etc.
This is not a subject that most Israelis wish investigated.

A grad student at Harvard was also interested: he thought it would be easy to check for increased IQ in carriers among Harvard students, many of whom are Jewish. But his enthusiasm decreased when his adviser - not a bad guy by the way - explained that doing this would make the student an "unemployable pariah" and get the adviser in trouble as well.

BGI, in China, is a big genomics shop, full of young and mathematically talented people, along with tons of new equipment. They're looking for alleles that affect cognition. That means ones that are important in explaining variation over the normal range (which we don't know much about), not ones that cause retardation (where we know quite a lot). A friend, a member of my secret army of the night, suggested that they should check out some Ashkenazi Jewish samples. They do, after all, have the highest average IQ of any ethnic group, and there are fairly strong hints suggesting that mutations in some of the characteristic Ashkenazi genetic diseases - many of which are neurological - may boost IQ in carriers. For example, if you have the Ashkenazi version of torsion dystonia,- your neurologist will talk about the muscle-spasm problems, which range from awful to trivial, and then try to cheer you up by pointing out that "it makes you smart".

But they didn't bite, for two reasons, First, largely because these guys don't know any theory and in fact know very little biology at all (as they freely admit), they didn't see why you might want to look at an outlier population like the Ashkenazi Jews, Second, the non math-geeks who run the place didn't want to do it, because they were afraid it would piss off the Jews. This in Beijing !

Parenthetically, it appears that IQ is highly heritable, especially in adulthood - at least in contemporary Western society. About as heritable as height. No single allele accounts for much of the variation in the populations studied so far (all European, as far as I know): instead variation between individuals, although strongly influenced by genes, is caused by hundreds or thousands of genes that each have a small effect. This in no way keeps a trait from being heritable. And since it is heritable, natural selection can cause changes in trait value. So could artificial selection. One suspicion is that rare deleterious mutations account for a significant fraction of the variation: this is looking more and more likely for things like schizophrenia and autism.

Let me say it again: if a trait is heritable, natural or artificial selection can change it. We don't have to know the genetic details (although it _is_ nice). The genetic influences can be one gene, a few genes, or many genes. Selection is still possible.

And what traits are heritable enough to be easily changed by selection? Virtually everything. Intelligence is highly heritable. Personality traits are moderately heritable, but still heritable enough that selection could easily change the distribution in a human over historic time. Strength, height, disease resistance, metabolism, etc etc.. all heritable.
About the only trait that is hard to select for is sex ratio: it's very hard to get a ratio that is very different from 50:50.
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