A gene called ROBO1 helps brain development, which can also lead to higher math scores, according to new German research.
This does not mean that being good at math is only genetic, or even that only one gene is responsible for being smart, but it does show that some level of intelligence and math ability is determined before birth.
The study, led by Michael Skeide from the Max Planck Institute for Human Cognitive and Brain Sciences, found that variations in the gene cause differences in grey matter volume, and these differences can be used to predict math performance.
It showed that ROBO1 controlled brain growth that was up to 20% responsible for mathematical ability.
Many human traits, such as intelligence, are controlled by a combination of genes and environmental influence, which makes it very difficult to predict. Traits like intelligence are hard to define and need to be broken down into specific activities to research.
Strong links previously have been found between genetics and math scores, but we did not know how these genes were helping with mathematical ability or what their role in the brain was.
Skeide and colleagues discovered that ROBO1 helps the layers of part of the brain, the cerebral cortex, to grow during foetal development. This affects the volume of a special area of the brain called the right parietal cortex, which is related to how well we are able to understand numbers and numeracy.
When the researchers tested the parietal cortex size of 180 children aged three to six and compared this to different variations of ROBO1, they found that the gene was directly linked to brain size.
Next, they tested math ability. Young children don’t have any mathematical training and are a little bit like a blank slate, so they were able to follow the children over the next few years of learning to see how well they performed in math tests and compare the results back to brain volume.
They also needed to make sure that children were not performing well because of another influence, so they studied children that had parents of different education levels. This helped them see if math scores were based mostly on brain size instead of having highly educated parents.
We already knew math ability was partially genetic, but this provides a reason how and why.
The findings are published in a paper in the journal PLOS Biology.