Is intelligence hereditary? Probably not. Is intelligence
innate? Quite possibly. These are the conclusions of a report published by the
European Commission under the somewhat unwieldy title 'Genome-wide association
studies, polygenic scores and social science generics: overview and policy
The dead live longer…
The possible correlation between genetic makeup and
intelligence and social success has long been the subject of heated
socio-political debate. These discussions always involved justifying ‘inequalities’ with regard to personal dispositions – or focusing
more on the importance of the environment for successful personal development.
was actually over in practice; the focus is now on attempts to reduce
inequalities through targeted educational and social policy interventions. The
emphasis on genetic predispositions was originally unable to gain a foothold because, other than studies on twins, it has not been possible to establish an
empirically robust link between a clear genetic deviation (in a particular gene) and personal
This now seems to be changing in the age of growing
computing and storage capacities and the availability of big data. Genetic variants are now no
longer isolated on one or a few genes, but rather in dozens or even hundreds of
individual variations (polygenic scores) using genome-wide association studies.
In this respect, the question of the hereditability of
certain personality traits is obsolete. It is extremely unlikely that a large group of individual
genetic traits will be passed on completely to the next generation. What
remains, however, is the interest in using them in order to make individual prognoses.
This involves finding answers to old questions about the genetic background of more complex traits
such as depression, intelligence, behaviour, confidence, income, political orientation, reproductive behaviour
(number of offspring), success at school, well-being, choice of career,
decisions in financial matters, longevity, willingness to take risks
(interesting for insurers), etc.
However, such links are always subject to misinterpretation of the purported correlations, because
the outcomes (social
success, etc) are not
the result of genetics,
but of the way the environment treats the person with that specific genetic trait, something which is liable to change.
Baby’s got blue eyes
...If all babies, unlike Elton John’s song, still had blue eyes in
adulthood, the thought experiment
used in the report to explain the phenomenon of environmental feedback loops or environmental reinforcement would be useless. However, it does
illustrate quite impressively how statistically correct genetic correlations, which are translated into
instructions for action without reflection, can turn into a self-fulfilling prophecy
(environmental feedback loop).
Let us assume that a certain genetic combination (polygenic
score) can be correlated with increased success at school. And further assume
that this combination codes for blue eyes. And finally, suppose that teachers
tend to prefer children with blue eyes. How do you deal with this knowledge?
Although the report is silent on this, several alternatives are possible:
- Limited public education
resources could be used more ‘efficiently’, especially for the benefit of
children with the above-mentioned characteristics. However, this type of
negative discrimination is also the most ethically reprehensible solution.
funds could be used specifically to support those who do not possess the
characteristic (positive discrimination).
- The teachers could be replaced (targeted manipulation of
The danger of misinterpreting correlations is especially high when certain
characteristics are concentrated in a ‘group’. The report deliberately avoids
the terms ‘ethnic origin’ or even ‘race’ which were still in use after WWII. If, for example, it turns
out that these characteristics are statistically significantly associated with
poor educational attainment, this is most likely due to the fact that the
members of this ‘group’ had inadequate access to educational institutions.
Political intervention would then have to start with that issue.
We’re not that far yet, but...
As the report acknowledges, even the best polygenetic scores
are currently unable to
provide useful insights into predicting the behaviour or future personality traits of an individual carrier. At best, genetic correlations seem to
allow some probability statements, but they are far from being biological/causal explanations.
... Policy makers are called upon to act
However, it is possible that one day more precise statements
on individual genetic potential will be possible. In view of rapid scientific
progress, the report recommends starting a broad dialogue on the effects and use of these new findings for the
benefit of all. This includes clarifying
the question of what type
of society we want to live in, especially given the danger of (negative) discrimination based on genetic information.
The report contrasts this with the vision of positive
discrimination in the sense of targeted solidarity and redistribution in favour
of those who have been given worse chances by the ‘genetic lottery’.
can be downloaded here.