Children are largely programmed at birth to pass or fail exams, a study suggests.
Evidence shows that school educational achievement is “highly inheritable”, say scientists. And many of the same genes involved influence exam performance across a broad range of subjects.
More than half of the differences seen between exam results may be due to variations in the DNA children inherit from their parents, according to the results.
Developmental psychologist Kaili Rimfeld, from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London, said: “Our findings suggest that many of the same genes influence achievement across a broad range of disciplines, moving beyond core subjects such as English and maths to include humanities, business, art and languages.
“For the first time, we found that these general genetic effects on academic achievement remained even when the effects of general intelligence were removed.
“We also found that over half of the differences between children’s educational achievement for all of these disciplines was explained by inherited differences in their DNA, rather than school, family and other environmental influences.”
The standardised curriculum used in the UK could help highlight the strong genetic influence, she added. Since all children had access to broadly the same education and took the same exams, environmental effects on performance were reduced.
The scientists analysed genetic data on 12,500 twins to investigate whether ‘nature’ or ‘nurture’had the biggest impact on GCSE results.
Comparisons of identical and non-identical twins are often used to untangle genetic and environmental effects.
Identical twins have the same set of genes, and would be expected to deliver much the same results if exam grades were purely genetically driven. In contrast, non-identical twins share only around half their genes.
Genetics is the science of inheritance, not predeterminism
The study, published in the journal Scientific Reports, found that academic achievement in English, mathematics, science, humanities, second languages, business informatics and art was influenced by the same genes. This was true even when adjustments were made to take account of genetic effects due to general intelligence.
All GCSE results were highly heritable. Genes, rather than environmental factors such as conditions at school and home life, explained 54 per cent to 65 per cent of the differences in performance between children.
Robert Plomin, another member of the King’s College team, said: “Understanding the specific genetic and environmental factors influencing individual differences in educational achievement – and the complex interplay between them – could help educationalists develop effective personalised learning programmes, to help every child reach their potential by the end of compulsory education.”
Other experts said the study should be treated with caution.
Darren Griffin, from the University of Kent, said: “It comes as no surprise that there should be a heritable component to exam success. The approach used in this study is a standard one demonstrating that monozygotic [identical] twins’ GCSE marks correlate significantly more closely than dizygotic [fraternal] twins.
“What we need to be careful of, however, is leaping to the assumption that this means that people are predisposed to do more or less well in their school exams. Genetics is the science of inheritance, not predeterminism, and there is no substitute for hard work and application.”