Monthly Archive for April, 2010

Although genetic factors make substantial contributions to reading performance, it is important not to overlook the contribtutions of teaching and the interplay between genetics and teaching, according to Jeannette Taylor and colleagues from Florida State University (Tallahassee, FL, US). Professor Taylor and the research team with which she’s affiliated used the oral reading fluency (ORF; simply words per minute) of twins’ (280 monzygotic and 526 dizygotic) classmates as a proxy for teacher quality, and the found that when twins were in classrooms where their peers were making lots of progress, the effects of genetic factors became more obvious: “Genetic variance in ORF was greater at higher levels of teacher quality.”

The bad news is that the reverse is true, too. Poor teaching, to the extent that it’s measured by gain in ORF, decreased the effects of genetics on reading growth.

Children’s reading achievement is influenced by genetics as well as by family and school environments. The importance of teacher quality as a specific school environmental influence on reading achievement is unknown. We studied first- and second-grade students in Florida from schools representing diverse environments. Comparison of monozygotic and dizygotic twins, differentiating genetic similarities of 100% and 50%, provided an estimate of genetic variance in reading achievement. Teacher quality was measured by how much reading gain the non-twin classmates achieved. The magnitude of genetic variance associated with twins’ oral reading fluency increased as the quality of their teacher increased. In circumstances where the teachers are all excellent, the variability in student reading achievement may appear to be largely due to genetics. However, poor teaching impedes the ability of children to reach their potential.

This is an especially interesting finding in light of the recent report, as noted over on LD Blog, that among twins with high IQs, the genetic contribution to reading is also more salient.

Taylor, J., Roehrig, A. D., Hensler, B. S., & Schatschneider, C. (2010). Teacher quality moderates the genetic effects on early reading. Science, 328, 512-514.

Link to “Teacher quality moderates the genetic effects on early reading.” It appears to me that this article is available to the general public. Note that there is also an interview with Professor Taylor; the narrator puts the point about teacher quality right squarely in front of the listener.