A study published this week reveals that the genes that determine how well a person reads also influences their math skills.
The study, released by British multidisciplinary journal Nature Communications, used 1,500 sets of 12-year-old twins from British families to look at the effects of genetic inheritance and environment on math and reading skills, writes Julia Rosen for The Los Angeles Times.
"Twins are like a natural experiment," said Robert Plomin, a psychologist at King's College London who worked on the study.
Plomin looked at reading and math test results of these sets of twins and compared them to those of unrelated children.
Identical twins share 100% DNA and fraternal twins share 50%. Environmental variables are shared. What they found were that the scores for each set of twins were two times as similar in identical twins as they were in fraternal sets. These results suggest that half of a child's ability to read and succeed in math comes from "generalist genes", working across a number of disciplines.
"If you found genes for reading," Plomin said, "you have over a 50% chance that those same genes would influence math."
The study does not suggest that the genes will influence how well students perform in these disciplines. What it does offer is insight into how the genes influence learning abilities and "how easily they learn to read and to do maths", according to Plomin. He also suggests the genes "are like little nudges" that may cause a person to read more.
"We don't want to pit nature vs. nurture," Plomin said. "But for parents who still think kids are a blob of clay that you mold to be what you want them to be, I hope this data — and there's tons of other data like this — will convince people to recognize and respect individual differences that are genetically driven."
The same genes may cause these skills to come with some difficulty for other children. "It's not that the child just isn't motivated, or that he's just not trying hard enough." The child simply needs some extra help to find the same level of success.
Environmental factors also come into play, even in sets of identical twins. One may have a different teacher who causes them to have a fondness for math while the other does not.
Douglas Detterman, an emeritus professor of psychology at Case Western Reserve University and editor of Intelligence who was not involved with the study, says that more research will be needed looking at the DNA of millions of people to better isolate the genes that affect our aptitude, writes Maanvi Singh for KPBS.
Detterman refers to teachers as farmers and children as their crop:
"You have corn plants that do well in certain environments, and don't in others. And the farmer's job is to get the corn plants into the right soil."
This could mean individualized educational approaches where students are allowed to learn at their own rate through different techniques. Plomin suggests a strategy similar to that in place in Finland, where schools do "whatever it takes" to give children the skills necessary to thrive in the modern world. This means smaller class sizes, extra hours of tutoring, and alternative learning approaches.
"Heritability does not imply that anything is set in stone – it just means it may take more effort from parents, schools and teachers to bring the child up to speed."