When it comes to factors
affecting children's school performance, DNA may trump home life or teachers, a
new British study finds.
"Children differ in
how easily they learn at school. Our research shows that differences in
students' educational achievement owe more to nature than nurture," lead
researcher Nicholas Shakeshaft, a PhD student at the Institute of Psychiatry
at King's College London, said in a college news release.
His team compared the
scores of more than 11 000 identical and non-identical twins in the United
Kingdom who took an exam that's given at the end of compulsory education at age
Identical twins share 100%
of their genes, while non-identical (fraternal) twins share half their genes,
Genetics rather than environment
The study authors explained
that if the identical twins' exam scores were more alike than those of the
non-identical twins, the difference in exam scores would have to be due to
genetics, rather than the environment.
For English, maths and
science, genetic differences between students explained an average of 58%the
differences in exam scores, the researchers reported. In contrast, shared
environments such as schools, neighbourhoods and families explained only 29% of
the differences in exam scores. The remaining differences in exam scores were
explained by environmental factors unique to each student.
Overall, genes had a
greater effect on differences in grades in science topics such as biology,
chemistry, physics (58%) than in subjects such as media studies, art and music
(42%), according to the study published in the journal PLoS One.
Heritability not fixed
None of this means that
students are destined to excel or doomed to fail, based solely on their DNA,
"Since we are studying
whole populations, this does not mean that genetics explains 60% of an
individual's performance, but rather that genetics explains 60% of the
differences between individuals, in the population as it exists at the
moment," he explained.
"This means that
heritability is not fixed – if environmental influences change, then the
influence of genetics on educational achievement may change too,"
While the findings may have
no implications for educational policy, it's important to understand the
important role that genetics plays in children's success at school, added study
senior author Robert Plomin, of the Institute of Psychiatry at King's College
"It means that
educational systems which are sensitive to children's individual abilities and
needs, which are derived in part from their genetic predispositions, might
improve educational achievement," he said in the news release.
The US Centres for Disease
Control and Prevention outlines the link between student health and academic achievement.