Genes Affect Reading Fluency, but So Do Good Teachers, Study Says

A study in the latest issue of the journal Science uses data on twins to explore the interplay between genes and the teaching environment when it comes to learning to read. The study found that, while genes do appear to account for a substantial portion of a child’s reading skills, having a strong teacher in the early grades makes a difference too.

“Children come into the classroom with individual differences,” said Jeanette Taylor, a clinical psychologist at Florida State University and the lead author of the study. “But that doesn’t mean that teachers don’t matter. Our study says they do. Teacher effectiveness can help maximize that potential.”

The study, which used data on more than 800 twins in Florida, examined reading scores for first and second grade classrooms that included those twins. Students were tested at the the beginning and end of the year on their oral reading fluency, or their ability to read words on a page without stumbling or getting stuck. By looking at improvement in scores among twins’ classmates, the researchers determined which teachers were more effective than others.

The study then compared how twins fared depending on which teacher they had through the year. If identical twins had different teachers but ended the year with identical test scores, for example, their learning would have been deemed to be fully dependent on their genes. But that’s not what the data showed. Instead, researchers found that effective teachers had a positive impact, elevating the scores above and beyond what could be attributed to genetic factors.

It’s worth noting, however, that Taylor and her colleagues did find genes to play a significant role in how well children could read. Other genetics researchers have published studies that attribute nearly all of a child’s learning gains to genetics instead of environment. That may fly in the face of what early educators have come to understand from their own research — that learning environments can make a large difference in children’s outcomes. Today’s study in Science forms an important bridge, hopefully one of many to come, between behavioral genetics and cognitive and developmental science.

“Our study is showing that it’s an interplay between genes and environment,” Taylor said. “The potential that your genes may give you will be maximized if you get to experience super, high-quality environments.”

The study is one of several articles in this week’s Science that are part of a special section exploring language and literacy.