There has recently been a lot of
dicussion about the award of a prestigious fellowship at Cambridge University
to Dr Noah Carl. I am not at all familiar with Dr Carl's work so not in a
position to make any comment at all on whether it give comfort and succour to
racists or eugenicists at the expense of scientific accuracy. Agreement broke
out, at least on my Twitter time line, that critics have every opportunity to
test rigorously his work as he uses openly available data. Which is an
excellent argument for open data, but that is another story (see my earlier
blog "In God we trust, the rest must bring data").
One direction in which the Twitter
exchange led, however, resulted in me feelinig that a lot of sociologits have
been leading somewhat sheltered live in terms of their familiarity with the
influence of eugenic ideas in neighbouring disciplines. I work with
epidemiologists. And the first thing one notices turning back to sociological
literature is that no sociologist has used the Registrar General's Social Class
schema (RG) for, oh, 30 years at least. Long ago, Gordon Marshall wrote of the
"eugenic assumptions" that underlie this classification and I have
also written a couple of blogs about this ("What is wrong with
"SES""). But in social epidemiology, after a move in a different
drection up to about 10 years ago , the use of measures and thinking that is
based on the same ideas as the RG classification has come roaring back.
All this has coincided with the
rise and rise of genetic epidemiology. Let me give a couple of quotes from
recent papers. Here is one from a paper in a high ranked journal called "Intelligence
in youth and all-cause-mortality: systematic review with meta-analysis"
published in 2011:
"Twin studies to determine the extent to which intelligence
shares genetic and environmental causes with health, education, and social
class, in predicting mortality, will also help to inform this issue. With
evidence of associations between cognitive performance and education showing
substantial heritability, it is possible that these variables may share some
genetic effects in predicting death."
Perhaps the recent paper that is
being most discussed is called “Gene discovery and polygenic prediction from
a genome-wide association study of educational attainment in 1.1 million
individuals” published in Nature Genetics this year. Here is a quote
from its Conclusions
For research in
social science and epidemiology, the polygenic scores
that we construct—which explain 11–13% and 7–10% of the variance in educational
attainment and cognitive performance, respectively—will prove useful across at
least three types of applications. First, by examining
associations between the scores and high-quality
measures of endophenotypes, researchers may
be able to disentangle the mechanisms by which genetic
factors affect educational attainment and cognitive phenotypes.”
The authors of this study were eager to avoid
misinterpretation of their findings. On the website of the Social Science Genetic
Consortium https://www.thessgac.org/ (stongly
recommended) are a large number of "FAQs" that had been raised about
the study, with associated sensible comments for example:
"it is important to
keep in mind that the score fails to predict the vast majority
(89%) of variation in years of education across individuals. Many of those with
low polygenic scores go on to achieve high levels of education, and a large
proportion of those with high polygenic scores do not complete college.
Thus, an important message
of this paper and our earlier papers is that DNA does not “determine”
an individual’s level of education, for multiple reasons: First, it is
estimated that, at least in the environments in which we have been measuring
it, the additive effects of common genetic variants will only ever predict
about 20% of the variance in educational attainment across individuals. Second, today’s polygenic
score is only able to predict a little more than half of that 20% (11
percentage points).
Thus
it seemed that “social genetics” (a term I hate) are too fascinating for many researchers
to avoid, is being carried out by responsible people. And indeed, the GWAS
studies have revealed important differences to the twin studies that have been
carried on for many years .
But I guess it was never going to stop
there. And in the last week or so a new paper has appeared: Genetic
consequences of social stratification in Great Britain by Abdel
Abdellaoui and colleagues, available at http://dx.doi.org/10.1101/457515 .
In their words:
We show that the
geographic clustering of genome-wide trait-associated alleles is related to
recent geographic movement of people and that the resulting regional genetic
patterns are associated with regional socioeconomic and cultural outcomes......
The strongest clustering was observed for Educational Attainment (EA). Among
the rest of the geographically clustered traits are body dimensions,
personality dimensions, and physical and mental health traits. ... Our results
show that people with a genetic predisposition for higher cognitive abilities
are leaving these (deprived) regions, likely attracted by better educational or
occupational opportunities in other regions. In fact, the people who were born
in coal mining areas and migrated to better neighbourhoods have higher average
EA polygenic scores than people born outside of these regions. The regional
clustering of cognitive abilities that follows may further affect the economic
development of neighbourhoods.
The
authors do go on to speculate that social policies might need to be devised to
lower the tendency of geographical mobility to increase differences in
deprivation between areas. If those with higher genetic scores for educational
attainment did not have to travel to more prosperous areas in order to get
better jobs and increase their income, the argument goes, this might slow down
the tendency of health inequalities between areas to widen over time.
A
clearly written cautionary commentary has also appeared in Nature at https://www.nature.com/articles/d41586-019-03171-6
But it is hard to escape the impression
of an element of dog-whistling in this literature. At the very least, sociologists
need to be on their toes in respect of it.
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