People are doing GWAS studies on alleles that influence educational achievement – IQ alleles, more or less – and are finding some. Once you find them, the natural question is how the frequencies of those vary in different populations. Do populations that test low on IQ have fewer plus alleles than those that test high?
This can get complicated, at least if the populations you’re comparing are highly divergent. If they are, the set of education alleles in one pop might be significantly different than the set in the other. Pygmies are like this with height: they share many of the alleles that affect height in Europeans, but also have some of their own. Of course, the most divergent human populations, Pygmies and Bushmen, are few in number and have no significant diasporas.
If all you want to know is the source of population differences, you can easily get around this: look at a mixed population and see how IQ varies with the degree of admixture.
Next question: what would be the implications of various possible results? Suppose that GWAS hits and admixture studies suggest that population ancestry did not matter. Every population is equal in genetic potential for intelligence. That would be a surprise – things sure don’t look that way. It would suggest that a potent and unknown environmental influence(s) was responsible for observed differences. I doubt this outcome a whole lot, but it’s a big universe.
Next possibility: the distribution of IQ alleles predicts what we already see. Those populations that test low have correspondingly low frequencies of plus alleles. Things are the way they look – no real surprises.
Last: things are mostly the way they look, but at least one population does a lot worse (or better) than you would expect from their measured IQ-allele frequencies. I think if you had done this 100 years ago there would have been some anomalies of this sort – populations with serious iodine shortages would have had anomalously low scores. If we hadn’t known about iodine shortages and their consequences, this kind of result would have hinted at it.
Next question: what would the impact of such results be?
For option 1: we would start looking hard for that indumbnifying environmental influence. We would want to be able to turn it off – or on.
Option II and III: Much would be explained. But the results would be almost entirely rejected. How many minds would be changed? Hardly any. You’d have to know a fair amount about genetics to even appreciate the evidence. No matter how sound the result, various bastards will emit a fog of lies about it – not many people would be able to see through that fog, and even fewer would want to. I know of a couple of cases in which people who were disinclined to believe in the results of twin studies came to accept them after GCTA results – extrapolating from that example, results like II or III would change the minds of hundreds of people worldwide.
This doesn’t mean that there would never be any consequences. There would eventually be practical applications of such a result, and the people working those applications would know and understand it.