To what extent can we tell this apart from the fact almost every university student leaves their hometown, to attend university?
https://www.biorxiv.org/content/biorxiv/early/2025/05/18/202...
Regional religiousness shows higher genetic correlations with personality (openness and conscientiousness) and less with SES and health traits than political preferences do, which implies additional dimensions of geographic clustering beyond high versus low SES.
Like say everyone tended to marry withing their own class at different points in history, they might tend to be more related to other people with ancestors in similar classes, than in societies that abandoned it.
Not endorsing it but would be interesting if past social systems affected DNA.
There's a famous paper where they map the first two principal components of a bunch of humans and get a map of Europe out.
Interesting!
Can you provide a link to this paper?
But yes the key message is, there is geographic clustering at genetic level.
I know the discussions are politically fraught. But if I understand the summary, your findings lean toward the determinism side. Is that fair? How do you think of the dichotomy? Thanks!
Absolutely not. I don't think any serious geneticist is a genetic determinist, in fact it's hard to even know what that means... DNA without an appropriate environment is nothing but a long stringy molecule!
In fact, the main impact of this paper was to help make geneticists aware that genes are confounded with geographic environments. That (plus much other research!) is one reason why researchers are now putting a lot of emphasis on family-based designs. In those, you can get truly causal estimates of the effect of a genetic variant or of a whole polygenic score, due to the "lottery of meiosis" that randomly give you genes from either your mum or dad.
Now you could equally argue that the paper shows geographic environments are confounded with genes. That's true too, though sadly a lot of social science still proceeds as if it wasn't the case.
Whatever genetic signal and influence is found between groups A and groups B, A and B are so highly variable within themselves that none of this is applicable to comparing individuals beyond a perhaps slightly weighed dice.
(wasn't suggesting that)
However, the randomness is great enough that first cousins do share approximately 1/8 of their genes, second cousins 1/32, third cousins 1/128 and so on. The rapid decrease of shared genes among relatives in successive generations also means that if mating in a population is really random, the population rapidly becomes homogeneous.
It is only assortative mating which generates and maintains distinctive subpopulations.
Most of my high school mates from a rural county who went to college never returned to a rural area. Those who stayed behind were disproportionately from the lower half of the class.
Before DNA analysis, anthropologists used language patterns as a signal of genetic relatedness.
The genetic divide goes more the other way - of course there’s going to be some positive selection for educational attainment/intelligence for people who left the village, but more generally the local populations are quite insular, migrate little (especially the ones who remain, of course - self-selecting), and have quite a few children, and in a population like that, you get genetic drift, resulting in more distinctive alleles compared to a generally larger mobile population, compared to the individual sedentary populations.
Where I live in Portugal this process has been going on for nearly a millennium - and you can tell if someone is from village X or Y 5km apart but separated by a river, just by looking at them - specific alleles get more and more prevalent in a small, largely closed population, quickly.
This doesn’t show that social mobility is broken - if anything, the opposite - it shows that a great many people have left the village and joined the mobile elite.
https://en.wikipedia.org/wiki/The_Son_Also_Rises_(book)
"The book follows relatively successful and unsuccessful extended families through the centuries in England, the United States, Sweden, India, China, Taiwan, Japan, Korea, and Chile. Clark uses an innovative technique of following families by seeing whether or not rare surnames kept turning up in university enrollment records, registers of physicians, lists of members of parliament, and other similar contemporary historical registers. Clark finds that the persistence of high or low social status is greater than would be expected from the generally accepted correlations of income between parents and children, conflicting with virtually all measures of social mobility previously developed by other researchers, which Clark claims are flawed. According to Clark, social mobility proceeds at a similar rate in all of the societies and in all the periods of history studied – with the exceptions of social groups with higher endogamy (tendency to marry within the same group), who experience higher social persistence and therefore even lower social mobility.[1][2]"
It seems just as likely, more likely, that nepotism and legacy networks are responsible for the continuation of certain families maintaining their social class.
However he’s an economist, not a geneticist. And the description of the book on Amazon focuses on last names and ancestry, not genetics.
https://www.amazon.com/Son-Also-Rises-Surnames-Princeton/dp/...
This book looks to me like it’s arguing that social policies don’t do much to affect familial networks, not that it’s arguing that the elites all have magical genes that keep them on top.
Other reasons are the specific predictions that a genetic explanation makes (exactly 50% contribution from males and females) which Greg Clark argues are borne out by the data; and the persistence through very different social regimes over long historical periods.
I should say that not everyone agrees, and this is just scraping the surface of the debate.
Consider that for each generation the genetics of the family founder are diluted by 50% (assuming that consanguineous relations are excluded). So after 5 generations or so, only ~3% of the heirs' DNA is specific to the family founder.
So, the fact that names per se better predict outcomes than DNA very strongly points to social factors as the major determinants.
It seems highly unlikely that each generation would be selecting on precisely the same genetic features of a particularly prominent family name. This is because that which provides social prominence is not consistent over time.
NB Class traditionally in the UK is not mainly about money...
Looks like the urban/rural divide in incomes and politics is actually stronger in quite a few ex-communist countries. Agree it would be interesting to see to what extent that's represented genetically, though I guess the picture is complicated by the amount of ethnolinguistic minorities eastern Europe has.
> ...Here we investigate the geographic clustering of common genetic variants that influence complex traits in a sample of ~450,000 individuals from Great Britain.... The level of geographic clustering is correlated with genetic associations between complex traits and regional measures of SES, health and cultural outcomes. Our results are consistent with the hypothesis that social stratification leaves visible marks in geographic arrangements of common allele frequencies and gene–environment correlations.
I've also seen papers that talk about the fingerprint of past wars, genocides, and migrations on the genome.
This study analyzed genetic data from ~450,000 British individuals and found that genetic variants associated with traits like educational attainment, personality, and health are geographically clustered across Great Britain, with the strongest clustering seen for education-related genes. The researchers discovered that people with genetic predispositions for higher educational attainment tend to migrate away from economically disadvantaged areas (like former coal mining regions), while those with lower genetic predispositions are more likely to remain in or move to these areas. This migration pattern based on socioeconomic factors has created visible geographic clustering of trait-associated genes that correlates with regional differences in education, health, income, and even political voting patterns - essentially showing how social stratification leaves genetic "footprints" on the geographic landscape.
There are "genetic predispositions" to higher learning? Don't tell the eugenicists that...
Your genes are what separate you from being a dog, so if you can do something a dog can't, like reading, you were predisposed to doing so by your genes.
You might think it's not like that, and there's some sort of discontinuity in it, but there's a genetically smooth way to arrive at the ancestors of you and a dog.and there is the exact same sort of genetically smooth way to go between any two humans, just with a much shorter path.