This Affects Your Ability to Do Well on Exams

This Affects Your Ability to Do Well on Exams

Differences in academic exam results are—to a large extent—explained by differences in people’s DNA

Could it be that genetic differences can affect how well children perform in exams? Our research suggests that this may well be the case and that individual differences between children are, to a large extent, due to the inherited genetic differences between them that predisposes them to do well academically, whatever the subject

We also found that there is shared genetic influence across a range of subjects, even after controlling the exam results for general intelligence

It goes without saying that children’s exam results at the end of compulsory education play a significant role in their future education and career paths. And it is also reasonable to assume that schools play a major role in school achievement. But children differ in educational achievement within the same school – and even the same classroom. This suggests that factors other than school or classroom differences explain the wide variation in pupils’ exam results

Our new research, published in Scientific Reports, examined the GCSE results, using classical twin method, that compares the correlations between identical and non-identical twins, and found that individual differences in exam results are to a large extent explained by the inherited differences in children’s DNA sequence.

We also found that many of the same genes influence achievement across a range of subjects – so, children who tend to do well in one subject tend to do well in others, largely for genetic reasons.

Previous research using data from the Twins Early Development Study (TEDS), found that there is substantial heritability for educational achievement in early and middle school years. Heritability is a population statistic, which describes the extent to which differences between children can be explained by the differences in their DNA, on average, in a particular population at a particular time.

So, for example, a heritability of 90%, means that 90% of individual differences observed in a group of people for a trait are explained by genetic differences between them and 10% explained by environmental factors. What it doesn’t tell us, is anything about an individual.

We already knew, based on our research which was published in 2007, (based on a UK representative sample of 7,500 twins pairs who were tested at the ages of 7, 9, and 12) that the average heritability for literacy and numeracy is almost 70%. In other words, more than two-thirds of the variation seen in academic test results is explained by genetic differences between children.

Further research from 2013 also found that educational achievement, as measured by standardised exams (GCSEs), at age 16 is also substantially heritable, with genetic factors explaining about 60% of the variance in results of the core subjects of English, mathematics and sciences.