Everything is different, but the same

Another new paper finds that the GWAS hits for IQ – largely determined in Europeans – don’t work in people of African descent. That was always a possibility: I’ve talked about it. If you look at the frequencies of height alleles (determined from GWAS in Europeans) you would predict that Pygmies are pretty short – but they’re considerably shorter than that. They have their own private alleles influencing height, which make them even shorter than you would think. Or, if you tried to estimate skin color in Koreans by the frequencies of variants that cause light skin in Europeans, you would conclude that they were black as night – but they’re not. They’re pretty light-skinned, but that’s caused by light-skin alleles common in East Asia, almost completely disjoint from the common light-skin alleles in Europeans.

So you can’t use those GWAS hits to tell how smart sub-Saharan Africans are, at least not today. All you can use are IQ measurements and achievements. It is as if the only way we could determine your height was by using a ruler, instead of GWAS predictions.

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17 Responses to Everything is different, but the same

  1. Cloudswrest says:

    It would be interesting to see how dark a European would look if you simply replaced just his light skin alleles with the corresponding Asian alleles on the same gene (presumably not for light skin). How about breeding a lot of hapas together and study the variance in skin color.

  2. whyteablog says:

    Related: thoughts on Piffer 2015?

    http://emilkirkegaard.dk/en/wp-content/uploads/PifferIntelligence2015.pdf

    Apparently they found that Asians generally have slightly more of the alleles that make a European smarter than another European. Hm…

  3. Rappaport says:

    Non Africans are more alike than Africans. So GWAS works for non Africans because genetic distance?

  4. James Miller says:

    This is very good news for IQ research because now when applying for funding researchers can claim that there is no way their research could be used to support certain negative stereotypes.

  5. Mike Eisenberg says:

    “So you can’t use those GWAS hits to tell how smart sub-Saharan Africans are, at least not today. All you can use are IQ measurements and achievements”

    Interesting possibility, but sketchy support. Consider the studies which have compared the predictive validity of education-related allele in Black and White American samples.
    Domingue et al. (2015): Add Health, sample age ~ 35; Predictors: Rietveld’s (2013) alleles. criterion: attained education & IQ. Correlations: Black r(Rietveld x IQ) = 0.15, r(Rietveld x education) = 0.11; White r(Rietveld x IQ) = 0.14, r(Rietveld x education) = 0.18
    This study (2017): HRS, average sample age >60; Predictors: Rietveld’s (2013) alleles & Okbay’s (2016) alleles; criterion: attained education. Correlations: Black r(Rietveld x IQ) = 0.05, r(Okbay x education) = 0.09; White r(Rietveld x education) = 0.16, r(Okbay x education) = 0.24.

    So, yes, these allele sets are poor predictors of education for, especially older, Blacks. But they are equally good predictor of IQ for younger Black and Whites. Whilst older Blacks could have a different genetic architecture for IQ, as they seem to for body mass, another possibility is that education was simply less meritocratically distributed.

  6. Commentator says:

    Implication is it would be worth repeating any large GWAS study with West Africans, East Africans, and probably Chinese, Melanesians and South Indians to capture more hits, if we’re interested in maximizing CRISPR potential. Another implication is existing proven genetic space of IQ boosting variants will be larger, so more optimism for making improving changes with low trade offs?

    (Might even be worth GWAS with Great Ape species who are much more genetically distant still… only I would doubt they have the population size for it, even if you sequenced all their genomes and captured all their behavioral data).

    • Cato says:

      I’ve wondered about this. All around me I see assortative mating–a Jewish academic marries a Chinese colleague; a Nigerian MD marries a WASP pharmacist… This is hybrid vigor, crossings from the most intelligent of their different lines. We should get offspring even more dazzling than the parents (Steve Jobs, Barack Obama, Bob Marley). Right?
      Actually, I wonder most about the Jewish-Chinese offspring. Someone should be tracking them.

      • gcochran9 says:

        Hybrid vigor isn’t an automatic thing. If the offspring of individuals from breed A and breed B do better than just the average of A and B, that’s hybrid vigor. It doesn’t always happen – usually the hybrid offspring are close to the average, sometimes they do worse than the average of the two parental groups. Sometimes it depends on whether the father or mother come from group A. When the progeny of A and B show an advantage, A and B are said to ‘nick’.

        Do any two human populations ‘nick’? Don’t know: clearly most do not, at least on most obvious traits. In principle two human populations might nick, though.

        Clearly, more research is needed – all possible crosses between different human populations. Andaman Islanders and Comanche.

  7. dave chamberlin says:

    I expect there is a lot of convergent evolution going on in genes that increase intelligence. That would explain part of this. I can think of no greater achievement in science than to explain the genetic component of IQ. I suspect it is a really tricky problem of three parts, additive meaning IQ boosting, subtractive meaning genetic load, and optimum combination.

    I appreciate your efforts to update us on the latest papers on this all important subject.

    • dave chamberlin says:

      Optimum gene combination, those combinations of alleles that have a result of a IQ above 145 will not be an easy problem to solve. I applaud Steve Hsu and company to take the IQ’s of geniuses and compare them to average people but i sincerely doubt they will get anywhere close to solid answers since they are only looking for alleles that by themselves add to IQ. Likewise I don’t think finding all those rare deleterious mutations and eliminating them will result necessarily in a high IQ individual. All it takes is one key gene and it’s back ups to work sub optimally for a non genius. The right question is being asked, what is the difference between a genius and an average person but we need to learn a lot more about brain function to answer it.

    • Dave chamberlin says:

      The book I can’t write but I would love to read is “Anger, Denial, and Reality Regarding IQ Diversity.” Here we have the essence of the gift that makes us human, that allows us our dominance and our comfort. That science can and should be exploring with great industry and enthusiasm. What do we get instead? Scorn and punishment for even looking at the subject area with scientific eyes.

      The whole subject area is taboo when racial differences are included. So avoid that emotional minefield. I want to know what creates the enormous spectrum in human brain function.

  8. hjkiphjkip says:

    How dark-skinned do you think Mesolithic W. European foragers were?

  9. Erik Sieven says:

    while those hits for IQ / gene interaction can thus not prove or disprove genetic racial IQ differences, they make the “no difference” hypothesis much less likely. The likelihood of the same difference reached by relatively different genetic paths is small, isn´t it? Convergent evolution does almost never produce identical phenotypes as far as I know.

  10. Pingback: More about Intelligence | POLITICS & PROSPERITY

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