Psychology Professor Jan Keenan has set out to answer a pressing question: To what extent are reading comprehension disabilities attributable to our genes and to what extent are they traced to our environment?
The answer to that question will undoubtedly have significant repercussions for parents, educators and students themselves.
Keenan’s research is part of a comprehensive inquiry into the causes of reading disabilities. It’s funded by the National Institutes of Health and conducted under the auspices of the Colorado Learning Disabilities Research Center, based out of the University of Colorado’s Institute for Behavioral Genetics. Keenan is one of several principal investigators, including DU Professor Bruce Pennington, working to determine the extent to which genes contribute to reading disabilities and whether environmental factors magnify the effects of genes.
To answer these questions, Keenan studies the reading behavior of fraternal and identical twins. In analyzing their reading, she looks at whether monozygotic (identical) twins are more similar to each other than their dizygotic (fraternal) counterparts. “If so,” she says, “that suggests a genetic basis to differences among individuals.” On the other hand, if dizygotic twins are very similar to each other and just as similar as monozygotic twins, “then that suggests that the basis of differences among individuals stems primarily from their family environment, which both MZ and DZ twins share.”
To date, Keenan and the other researchers have tested about 800 twins. Although more research needs to be done before definitive conclusions can be reached, preliminary findings indicate that reading and comprehension disabilities are largely genetic. In fact, the molecular geneticists on the research team have zeroed in on the likely culprit: some genes on chromosome 6.
For parents, this news often comes as a relief, Keenan says. Many of them have held themselves accountable for a child’s reading problems, assuming that if only they had made additional forays to the library, the story would read differently.
Still, Keenan hopes that parents and educators remain optimistic about improving children’s reading comprehension. Her research is beginning to suggest that comprehension in students with reading disabilities is enhanced when students are reading about familiar materials. “What I see in our work right now is that if children have a lot of prior knowledge on a topic, it can help them immensely,” she says.
“In addition to teaching explicit strategies for decoding and comprehension, we can help children’s reading by enriching their environments so that what they are reading about is somewhat familiar,” Keenan explains. “Familiarity with constructs makes reading easier.”
For educators, that might mean supplementing textbooks with films or visuals. It might mean trips to museums or visits from guest speakers.
“We tell the parents, just because a lot of this child’s reading behavior is influenced by the genes, that doesn’t mean there is nothing to be done,” Keenan says.