With this paper, we ended up showing how social stratification in a modern meritocracy makes it increasingly less likely that someone close by shares recent ancestors with you and more likely that they share a genetic talent for socio-economic success.This is, to put it bluntly, eugenics. The paper in question shows nothing of the kind. In my view, in fact, it shows the opposite; that this is not a "modern meritocracy," and I think that holding such a belief is a sure tip-off of the biases of the authors in their rather misguided and disturbing conclusions.
Let's take a look at the study with a starting point of assuming that all of the genetic variation seen in "Educational Attainment" is related to population stratification and assortative mating that confounds GWAS (particularly in the UK BioBank).
The premise of this unfortunate study is that people with particular genetic variations are more likely to attain higher education and, subsequently, more likely to move out of lower socioeconomic areas to areas with more opportunity for the those with higher intelligence, and this is genetically driven behavior. So, let's see how they make their case, starting with this:
Regional differences in allele frequencies are driven by genetic drift (that is, the random fluctuations of allele frequencies in each generation), natural selection pressures, migrations or admixture (that is, two previously isolated populations interbreeding). Out of these four mechanisms, genetic drift is the only mechanism not expected to disproportionately affect genetic variants that are associated with heritable human traits. Natural selection targets heritable traits over extended periods of time, thereby affecting allele frequencies of the genetic variants that are associated with the traits under selection. Earlier studies have identified natural selection pressures on many trait-associated variants by looking for extreme allele frequency differences between different ancestries.So, without any real evidence other than "Earlier studies have identified natural selection pressures on many traits..." , they claim that "natural selection" is playing a role and not just genetic drift. The fact of the matter, of course, is that there is no such thing as "natural" in such a selection among human beings in a structured society. People choose mates in the same social class they are in. This is particularly true in Great Britain, which has a long history of an aristocratic social stratification. Thus, you are going to find differences in genetics that perhaps in part will stratify geographically, but will also be related to social class across the country. Are people more likely to marry someone who lives near them or someone in who is in the same social class? So the fact that someone lives in a lower SES geographic region, does not mean that they are going to ignore the social class they are in and this will perpetuate certain genetic similarities that will serve as markers of their particular social class in the same way that variants might indicate someone is Irish, or German or Chinese, without any need to assign a purpose behind these genetic variants. They are simply markers unless demonstrated otherwise.
Next, the authors make a case for people leaving lower socioeconomic areas because they have genes that drive them to do so:
Migration is a behaviour, and since most behavioural traits have heritable components, migration is likely to be associated with genetic variants that influence behaviour. Long-distance migratory events may in turn result in admixture. Internal migrations (that is, migrations within countries) may lead to geographic clustering of trait-associated genetic variants beyond the clustering of ancestry, and may occur for a variety of reasons. They may be driven by the search for specific neighbourhood, housing and inhabitant characteristics, and/or socioeconomic, such as the mass migrations from rural to industrial areas during industrialization. These geographic movements may coincide with the regional clustering of a range of heritable outcomes such as socioeconomic status (SES), health and cultural outcomes."Migration is a behaviour," is a rather bizarre assertion. It implies people have some kind of "desire to migrate" genes and act on that. The reasons for migration are generally economic in nature and aren't due to the fact that these people like to migrate (as is noted by the authors), however, they seem to be adding the idea that the SES of the individuals migrating is genetic. This is circular: They migrate due to their SES, which is genetically driven, so they migrate because of their genes.
Again, if you are in a certain social class, in a stratified society, the members of your social class will have some similar genetic variants unrelated to why they are in that social class (excepting obvious genetic indicators related to things like skin color and other physical characteristics). Thus, you are not saying anything about the genetics of people who migrate. People in higher socioeconomic classes tend to migrate to areas where they will have more opportunities and people in lower socioeconomic classes will migrate (or not migrate) for their own economic reasons. It has nothing to do with their incidental genetic similarities.
Next noted in the study is this:
In particular, EA, body fat, BMI and overall health showed considerable clustering in coal mining areas, as further discussed below. Without controlling for ancestry, 30 out of the 33 polygenic scores tested showed significant geographic clustering, with geographic distributions similar to ancestry differences captured by the PCs ... with EA polygenic scores showing the highest Moran’s I values...A finding like this, that EA clusters more than most any other trait, should tip you off that you live in a very stratified society rather than a meritocracy. The fact that it makes the authors surmise that it is more genetic in nature than other traits, even such things as height and obesity, is curious. The authors take it a step further and point out that individuals living in coal mining areas with higher EA polygenic scores were more likely than those with lower EA polygenic scores to move out of the coal mining regions, suggesting then, that this was a genetically-driven phenomena. Again, in a stratified society, in which opportunity for educational advancement is driven to a large degree by social class (and the educational achievement of one's parents), individuals in a social class with high EA, will have higher polygenic scores for EA due to assortative mating, with little to do with any perceived function of the SNP's used to construct that polygenic score. This is circular again: People with high educational attainment tend to have genetic markers due to being in a closed social class, so it must be their genes. There is really nothing different being shown when those with a high polygenic score for EA tend to move out of coal mining areas, vs those with a high socioeconomic status tending to move out of coal mining areas. It is little more than a pedantic way of saying it, and no more valid than saying that people with genes common in those with Italian heritage tend to like spaghetti more than those with genes common in those with Portuguese heritage. This is probably true, but has nothing to do with the genetic variants themselves.
The whole process of looking at populations through differences in genetic variants could be interesting, if one were to discard the assumption that the differences in "phenotypes" like EA, intelligence, mental disorders, voting habits, etc. were due to the gene variants themselves, rather than an indicator of how a society has been stratified and how this effects opportunities.
To conclude:
This study shows:
1. People in higher socioeconomic classes with more opportunity for advancement, are more likely to move to areas in which they could take advantage of the opportunities that provides and, likewise, those who are in lower socioeconomic classes are less likely to move, barring some economic opportunity.
2.Those in higher socioeconomic classes are more likely to have better nutrition and less obesity.
3. AND - there is enough stratification and assortative mating in the UK that we can identify genetic variants more common amongst those with high (or low) EA.
In other words, it shows nothing new.
What it does not show:
1. That EA is causally related to some SNP's.
2. That "Great Britain is a meritocracy." (I'm imagining some pompous Lord saying that with the usual affectation).
3. The Brexit Gene
I have little interest in the motivations of those who perform these studies, when they try to distance themselves from whomever is going to take this kind of research and project it onto their racist ideas. This is already being done the same day it was published, with the usual crowd of race scientists claiming that there is a "genetic drain" in lower socioeconomic areas. These studies create a harmful and false perception that our lot in life is related to our genetics, rather than a stratified society.
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