A controversial study on twins claims to provide strong evidence that genetic inheritance has a bigger impact on exam success than schooling and parenting. Does this mean that a child鈥檚 educational fate may be sealed at conception? Or that a child鈥檚 genes might be analysed to determine how they are taught? 快猫短视频 finds out.
What did the study actually discover?
The study was designed by of the Institute of Psychiatry at King鈥檚 College London and his colleagues, to tease apart the impacts of genes and the environment on educational achievement.
The key objective was to see how exam scores varied from the national average depending on whether twins had the same genetic make-up, which identical twins do, or shared only half of their genes, which is true for non-identical twins.
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Since each set of twins in the study was assumed to share the same environment and schooling, the researchers were able to separate the effects of genetics and education on their academic success.
It turns out that nature trumps nurture. After analysing the results of 5474 pairs of twins 鈥� 2008 of them identical 鈥� the team found that genes accounted for 52 per cent of the differences between exam scores. A shared upbringing accounted for only 36 per cent of the differences, with the remainder accounted for by environmental factors that weren鈥檛 shared, such as each twin having a different teacher.
Did the result hold true for every subject?
Overall, across the three core subjects of English, mathematics and science, achievement was 58 per cent determined by genetics. Individually, achievement was 52 per cent down to genetics for English, 55 per cent for maths and 58 per cent for science.
The figure for humanities was lower at 42 per cent. This was a surprise to Plomin because, traditionally, excellence in humanities subjects such as art or music is considered to be 鈥渉anded down鈥� from parents, whereas science is considered a product of the teaching environment.
Does this mean that the die is cast for children whose parents haven鈥檛 done well in their exams?
Not according to Plomin. 鈥淔inding a genetic influence does not mean we cannot do anything about it,鈥� he says. 鈥淢arginalisation of the 鈥榣ess gifted鈥� does not at all follow from finding genetic influence on educational achievement. If anything the opposite is true 鈥� we need to provide more resources for those who need the most help.鈥�
So, should we change our education systems based on these results?
Plomin says it is far too early to say, but the findings should inform debate on how education is delivered and structured. 鈥淲e believe in an evidence-based education, and we don鈥檛 yet know what works best,鈥� he says.
Plomin favours an educational system that gives extra resources to struggling children to optimise their genetic potential. He thinks that each child鈥檚 genetic make-up prompts them to react differently to their schooling so, ironically, attempts to level out differences in achievement by providing a uniform education system 鈥� like the UK National Curriculum 鈥� actually achieves the opposite. For example, children whose genetics give them the motivation and aptitude to read early zoom ahead of others.
But Plomin argues that children of all abilities can achieve this, provided they receive extra help to do so. 鈥淥ne strong implication of recognising and respecting genetically driven differences between children is to personalise education as much as possible, rather than imposing a 鈥榦ne-size-fits-all鈥� approach,鈥� he says.
However, even if it were possible to analyse every child鈥檚 genetics, no single genes for IQ or educational achievement have yet been identified, says Sarah Norcross of the Progress Educational Trust, a UK charity that promotes debate on genetics and reproduction.
Most studies so far, including those by Plomin, have found that educational achievement is influenced by a combination of thousands of genes. 鈥淲e don鈥檛 even understand the genetics of height yet, which is very easy to measure,鈥� says Norcross. 鈥淪o we are light years from applying this type of thing to education.鈥�
What do others make of the findings?
Some researchers are sceptical, including Steven Rose of the UK鈥檚 Open University, who is critical of twin studies and of attempts to find genes linked with intelligence. He says that twin studies are 鈥渘otoriously subject to difficulties of interpretation鈥�.
For instance, the unusual upbringings of identical twins 鈥� often wearing exactly the same clothes or being confused with one another 鈥� constitute an environmental impact that could be overlooked when comparing them with fraternal twins. But he agrees with Plomin that child-focused rather than rote education is the way forward. 鈥淚n an ideal school environment, individual aptitudes should be encouraged, but you don鈥檛 need to, and nor would it be practicable to sequence a child鈥檚 genome to discover what these aptitudes might be,鈥� he says.
鈥淪ome people might take the results negatively, as if our potential in life is limited by our genetic code,鈥� says Paul Thompson of the University of Southern California in Los Angeles, who has previously reported the discovery of genes linked with IQ. 鈥淏ut you can interpret the study positively, as we need to seek out a person鈥檚 natural talents to help them fulfil their potential.鈥�
