Modeling the Etiology of Individual Differences in Early Reading Development: Evidence for Strong Genetic Influences.
We explored the etiology of individual differences in reading development from post-kindergarten to post-4thgrade by analyzing data from 487 twin pairs tested in Colorado. Data from three reading measures and one spelling measure were fit to biometric latent growth curve models, allowing us to extend previous behavioral genetic studies of the etiology of early reading development at specific time points. We found primarily genetic influences on individual differences at post-1stgrade for all measures. Genetic influences on variance in growth rates were also found, with evidence of small, nonsignificant, shared environmental influences for two measures. We discuss our results, including their implications for educational policy.
Department of Psychology and Neuroscience, and Institute for Behavioral Genetics, University of Colorado Boulder.
Micaela E
ME
Christopher
Department of Psychology and Neuroscience, and Institute for Behavioral Genetics, University of Colorado Boulder.
Jacqueline
J
Hulslander
School of Behavioural, Cognitive and Social Sciences, University of New England, and Department of Behavioral Sciences and Learning, Linköping University.
Brian
B
Byrne
Department of Behavioral Sciences and Learning, Linköping University.
Stefan
S
Samuelsson
Department of Psychology, University of Denver.
Janice M
JM
Keenan
Department of Psychology, University of Denver.
Bruce
B
Pennington
Department of Psychology and Neuroscience, and Institute for Behavioral Genetics, University of Colorado Boulder.
John C
JC
Defries
Institute for Behavioral Genetics, University of Colorado Boulder.
Sally J
SJ
Wadsworth
Department of Psychology and Neuroscience, and Institute for Behavioral Genetics, University of Colorado Boulder.
Erik
E
Willcutt
Department of Psychology and Neuroscience, and Institute for Behavioral Genetics, University of Colorado Boulder, and Department of Behavioral Sciences and Learning, Linköping University.
Richard K
RK
Olson