A new study of twins is the first to show that environment plays a key role in reading growth over time.
Stephen Petrill, lead author of the study and professor of human development and family science at Ohio State University, said that the results give further evidence that children can make gains in reading during their early school years, above and beyond the important genetic factors that influence differences in reading.
"We certainly have to take more seriously genetic influences on learning, but children who come into school with poor reading skills can make strides with proper instruction.
"The findings support the need for sustained efforts to promote reading development in children that take both genetic and environmental influences into account," Petrill added.
While other studies have shown that both genetics and environment influence reading skills, this is the first to show their relative roles in how quickly or slowly children's reading skills improve over time.
The study participants were 314 Ohio twins participating in the Western Reserve Reading Project. This study included 135 identical twins and 179 same-sex fraternal twins.
The study appears online in the Journal of Child Psychology and Psychiatry.