I disliked and feared maths for most of my school career and dropped it as soon as I possibly could. My mother recalls me crying as a five-year-old because: “I can’t do the people-on-the-bus sums”. If the bus has 12 passengers and three get off, how many are left? English, by contrast, was a breeze. At seven, I stood on a chair with a microphone and read my version of Sleeping Beauty aloud to the entire school. Reading and writing already ranked high among my passions.
Mine isn’t an unfamiliar tale. Many people label themselves as “not a maths person” or “not much of a reader”, often while they are still children. And yet, in a recent study published in Nature Communications, scientists showed that around half of the genes that affect how well 12-year-olds in the UK perform in maths also affect how good they are at reading. And they showed this in a new and important way.
For the first time ever, this study – led by UCL’s Oliver Davis, Chris Spencer at Oxford and Robert Plomin at King’s College London – was able to estimate genetic influences on learning abilities using DNA alone. The implications of this for future genetically sensitive research in the behavioural and social sciences are highly significant. It is certainly much easier to get hold of DNA than it is to get hold of a results from a large twin sample – another good way of researching this area.
Overlapping genes for maths and reading
The researchers analysed millions of DNA variations from almost 3,000 people and found that more than half of the differences between how well 12-year-olds performed in reading and maths could be explained by differences in their genes. But they also found that reading and maths are correlated partly for genetic reasons: many genes appear to operate in both domains.
These results are not in themselves new. Twin studies have previously reached very similar conclusions. However, the fact that such findings have now been confirmed by a genome-wide association study – where many common genetic variants are explored for association with a particular trait – is a very significant development.
It is interesting that in spite of using DNA data no particular genes emerged as significant influences on reading or maths. Instead, the researchers found collections of subtle DNA variations.
This ties in with other research that has led to an understanding that many genes of small effect combine to influence complex traits and that the effects are mostly too small to pick up reliably, even with large samples. With genes it seems we’re more likely to find teams than star players.
The research supports the Generalist Genes Hypothesis, the idea that genes are generalists and environments are specialists. Twin studies have found a great deal of evidence that important environments are likely to be specific to particular traits or learning outcomes. For example, a good English teacher might have a slightly different profile to a good maths teacher. The two subjects might benefit from different approaches to homework or different classroom organisation. They may, in short, need to offer different ways of drawing out genetic potential.
Environment still hugely important
What we have here is compelling evidence that genes influence maths and reading abilities and that at least half of the genes influencing one ability also influence the other. So, in that case, how can it be that some kids are so much better at reading than maths, and vice versa?
The first answer is simply that genes do not determine behaviour. Genes offer probabilities rather than prophecies. They represent “what is” rather than “what could be”. Even if you have the capacity to do well in a subject this does not automatically translate to high achievement. Motivation, confidence and interest all have a role to play too.
The second answer is that the genetic overlap between the two skill-sets is not 100%. Although there is evidence for shared genetic effects across reading and maths there is evidence of some genetic specificity too.
Most importantly, this new study highlights the role of the environment. It would appear that our life experiences have a particularly important part to play in making some people better at one subject than the other. This may happen through a variety of mechanisms including sparking an interest, inspiring future aspirations or nurturing appetites as well as aptitudes. Both genes and experiences influence the choices young people make about further education and careers and cannot be considered in isolation from each other.
The UK government has been pushing recently to improve national mathematics performance, and bring them up to levels seen in East Asia. Shared genetic influence on reading and maths suggests that if average maths performance lags behind average reading performance then this should, from a biological point of view, be possible.
The key to achieving this, however, lies in our environment rather than in our DNA. We need a better understanding of which aspects of the maths learning environment promote traits such as self-efficacy, interest and effort as well as achievement – and which don’t. We also need to understand that the same approach will not work for everyone. Drawing out individual potential requires at least a degree of personalisation.
And, just for the record, yes I can do the “people-on-the-bus” sums now.