The influence of genes on education, a study on 11000 twins in the UK

Via @fanseel I discovered this new study that can spur a lot of attention and discussion. Or what do you think when you read that heritability was substantial for overall GCSE performance for compulsory core subjects (58%) in the UK.

Let’s first take a look at the abstract:

We have previously shown that individual differences in educational achievement are highly heritable in the early and middle school years in the UK. The objective of the present study was to investigate whether similarly high heritability is found at the end of compulsory education (age 16) for the UK-wide examination, called the General Certificate of Secondary Education (GCSE). In a national twin sample of 11,117 16-year-olds, heritability was substantial for overall GCSE performance for compulsory core subjects (58%) as well as for each of them individually: English (52%), mathematics (55%) and science (58%). In contrast, the overall effects of shared environment, which includes all family and school influences shared by members of twin pairs growing up in the same family and attending the same school, accounts for about 36% of the variance of mean GCSE scores. The significance of these findings is that individual differences in educational achievement at the end of compulsory education are not primarily an index of the quality of teachers or schools: much more of the variance of GCSE scores can be attributed to genetics than to school or family environment. We suggest a model of education that recognizes the important role of genetics. Rather than a passive model of schooling as instruction (instruere, ‘to build in’), we propose an active model of education (educare, ‘to bring out’) in which children create their own educational experiences in part on the basis of their genetic propensities, which supports the trend towards personalized learning.

When discussing the influence of genes and education, many people get an ichy feeling to say the least. but the very last paragraph of the open access article is one everyone wanting to start a nature-nurture discussion should read:

“In closing, we note that accepting the evidence for strong genetic influence on individual differences in educational achievement has no necessary implications for educational policy, because policy depends on values as well as knowledge. For example, a deep-seated fear is that accepting the importance of genetics justifies inequities – educating the best and forgetting the rest. However, depending on one’s values, the opposite position could be taken, such as putting more educational resources into the lower end of the distribution to guarantee that all children reach minimal standards of literacy and numeracy, so that they are not excluded from our increasingly technological societies. It is to be hoped that better policy decisions will be made with knowledge than without. Part of that knowledge is the strong genetic contribution to individual differences in educational achievement.”

9 thoughts on “The influence of genes on education, a study on 11000 twins in the UK

  1. Ook bijdrage over hetzelfde onderzoek in The Guardian. Nu al honderden reacties. We citeren even enkele’ sympathiserende’ reacties.
    At one level, the inheritance of cognitive ability (e.g. language, memory, reasoning) is obvious. Regardless of where you look in the world, human beings rapidly outpace other species of animal in terms of cognitive functioning (in most areas at least). This suggests that human intellect has evolved and therefore influenced by genetics.
    The misconception (bordering upon profound ignorance) is that this intellect springs from the womb fully formed. It does not – and it’s obvious when you think about it. Mozart would never have composed a thing if he had not been exposed to music and had access to musical instruments. Stephen Hawking would never have developed his ideas about black holes without being exposed to the ideas of modern physics and mathematics. Cognitive development, at a fundamental level, requires stimulation from and interaction with the environment.
    What Plomin’s research appears to show (if we take such twin studies at face value and ignore the validity issues associated with them) is that social and educational inequalities still determine a significant component of educational outcome. As it is, Plomin’s research does not undermine the importance of the quality of schools or investment in education for all – it actually underlines it.
    What is important about education is that it provides equal opportunities to develop cognitive abilities. What we should be striving for is equality in the opportunities afforded to children to develop their cognitive abilities regardless of the socio-economic status of their parents. When we reach the point where the only variation within children’s academic attainment is their genetic traits, then we can fairly say we have a perfect education system.
    After all, if the only measurable difference in educational outcomes was genuinely down to genetic inheritance, then we could honestly say we were developing all children to their full potential.
    2. sellramsey RockyFjord
    If physical characteristics such as height, hair and eye colour or nose size can be passed from parent to offspring, why should it be controversial that parents with more complex brains often pass this physical characteristic on to their offspring?
    3. dleyBaxton
    This study is excellent news, as hard evidence is gathered that clearly shows that genetics is the most important factor in academic performance, and not environment, which, let’s face it only confirms what IQ scientists were saying for decades, we can now finally address the issue of proper funding for schools.
    The problem with reactions to this article, as always, is that the general population is not familiar with the analyse of variance statistics on which it is based, and its limitations.
    While twin studies may have some technical problems, these are minor compared to the effects of their misinterpretation. So here goes another attempt, to add to that of Michael Reiss, mentioned above: what has been found here is that approximately 50% of the VARIANCE (one measure of population variation) in one particular behavioural characteristic is heritable. This is not surprising, as genes build biochemicals build nervous systems, and it is in the same ball-park as many studies of the heritability of various human behaviours – including an entirely different set of measures collectively called IQ.
    But, first, this says nothing about any one individual (i.e. it is not saying that 50% of Sally’s ability is ‘from her genes’).
    Second, and most important it does not say ANYTHING about the potential effect of teaching to change the measured behaviour. There remains 50% of the population variation to play with even within the exact historical circumstances that framed this study.
    Lastly, and most important, it does not say ANYTHING about what results we would expect if we changed the environment to which the students were exposed.
    So, the results are not invalid, nor are they surprising, they fall into line with many other studies, and they say NOTHING about the effect a teacher, and more importantly a parent, can have upon the achievements of a child. In contrast, probably all of us know from our own experience just what a difference a good teacher or a good parent can make.
    5. lkklkll
    To everyone who is saying these results are suspicious, these results are entirely consistent with previous research on this topic, and there is hardly anything new here that was not known before.
    Other studies have measured heritability of educational achievement and IQ and the results very consistently hover around 50% genetic influence, with shared environment being significantly less, and the remaining unknown causes also being significant. (“unshared environment”)
    The methodologies of other studies have included other ones like this (twins reared together), and other methods such as studies of twins reared apart, adoption studies, and studies that use gene sequencing to directly compare genetic similarity to similarity of outcomes in unrelated individuals. All these diverse methodologies give numbers around 50% for heritability of IQ, so it is quite well established, and has been for decades.
    6. Sarah614
    The study shows that environment is more important than anything else. If that was the case then the results would have been different. It is not necessary to separate identical twins to demonstrate the relative impact of hereditary and environmental factors as these show up in a comparison of DZ and MZ twins. Moreover studies of separated identical twins have shown that these twins grow up to be be highly similar despite different environments. It is a common misconception that environments need to be exactly equal for these results to be valid. As long as children have access to universal education and are not starved and beaten everyday then they share a common enough environment for this kind of study. Of course parental wealth and education play a part in outcomes however they only play a small part. It is important to remember that twenty years of research on twins, adoption studies and siblings has shown that the effects of environment are highest in children and actually reduce in adults. That is by 18 the 50% figure, for genetic variance, has increased to more like 75%.
    7. ZR8
    We have moved from an era where genetics didn’t have much impact (inherited wealth and status) to one where what you do yourself is what matters (ie a meritocracy). And the more equal the opportunity, the more pronounced the impact of innate talent will become. The element of chance is reduced. So now you see the consequences as this feeds into social behaviour. High performing, high earning individuals marry each other and raise their kids in highly nuturing households. It is not random, it becomes self selecting. This new upper middle-class becomes self-sustaining and replicating – they are the ones that can afford to have multiple kids, use private schools etc.
    If you looked at the performance of children from these families you will see a high degree of heritability from their parents – the effect of environment is virtually eliminated. There is no way to counter this, the scale of the effect is too great to overcome with tinkering with schools or some form of discrimination.
    8. XYZ
    At my kids school I see families with 4, 5 or even 6 kids – all of whom are geared up for Oxbridge or similar. The parents are barristers, consultants, business owners – whatever. They have ability, and their kids have it in spades. What do you do if you achieve equality of opportunity, only to find equality of outcome has receded into the far distance? Because that is exactly what is happening. It can only get more pronounced.
    9. Mudhutter
    At first I was ready to wade into the notion that genetics made such a difference, but having digested the article and cooled down a bit, I can see that they have proved that this is the case. Otherwise why doesn’t everybody in the class perform the same, where are the differences in kids’ performance coming from? By studying identical and non identical twins they have been able to eliminate the percentage that is attributable to environmental factors, leaving the rest to genetic factors. It’s only like any other ability, how much your dad earns doesn’t affect your musical or sporting ability. It’s the same with your learning ability.
    Pretty clear from this argument that some people don’t want Plomin’s argument to be right, because it doesn’t fit the way they like to see the world. I personally don’t care whether he’s right or not – I want the truth, whether it fits the way I see the world or not. For the Left, any mention of intelligence is a red rag, and any idea that it is really important is, to borrow a phrase, “an inconvenient truth”.
    Boris, to be fair to Boris, was arguing for more attention to be paid to those whose intelligence did not equip them to join the intellectual high fliers. I’m not sure I agree with him as to who creates wealth, but he was actually arguing for less inequality – not for equality, but for less inequality.
    I think there is more than an element of truth in the study. How should this impact policy? its very important to make sure that everyone get an opportunity to succeed in what they are interested in. We need to get away from the idea that everyone is born with an identical ability and the rest is completely shaped by nurture (even though a lot is shaped by nurture).
    It would be stupid to have a system where those perceived to be at the “bottom” of something are made to feel like pariahs. I don’t anyone has a monopoly in talent and intelligence, someone could be excellent at mathematics but useless at music or sport. Life would be boring if we were all the same? all of us have evolved for 4 billion years so I am sure we can evolve further; even the most basic yob can make progress.
    12. Andrew Street
    The figures fit in with the general consensus that what we ‘are’ is down to about 60% nature and 40% nurture, and are not therefore groundbreaking exactly.
    What is important is that all children are encouraged to be the best they can, because 40% is still a high figure, and there are all kinds of talents and abilities. As for who will clean the toilets: in the future, robots.
    13. Sarah614 radiantflux
    The study compares twins who are more closely related to twins who are less closely related. If identical twins have more similar exams scores to non identical twins who in turn have more similar exam scores to siblings despite the fact that they all share the same family and most likely school then this is evidence of the relative importance of genetic factors. This is the basis of twin studies. The results of this study simply replicate twenty years of research. It is also corroborated by adoption studies that show educational outcomes for adopted students are highly correlated to their birth parents and not correlated to heir adoptive parents. This is true even where the adoptive parents are much richer and better educated than the birth parents
    And in fact it is common sense. No-one who actually went to school thinks every child has the same abilities or is of the same intellect. Some children are innately bright, and do better in exams with less effort. This is blindingly obvious to anyone. It is not surprising that a lot of this innate ability is determined by genes.

  2. […] Ook opvallend in het onderzoek is dat ze keken voor welke vakgebieden ouders het meest en het minst effect hebben. Hier blijkt dat je met kunstvakken de grootste invloed ziet, vervolgens taal, maar waarbij de invloed voor de andere vakken direct relatief klein wordt (denk aan lezen, wiskunde of een andere taal leren) en waarbij voor wetenschappen het effect van helpende ouders… zelf negatief zou zijn. Dit ligt trouwens in lijn met het Britse genenonderzoek dat aangaf dat welke vakken het minst erfe…. […]

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