Stefan Samuelsson|Brian Byrne|Richard K. Olson|Jacqueline Hulslander|Sally J. Wadsworth|Robin P. Corley|Erik G. Willcutt|John C. DeFries
Response to early literacy instruction in the United States, Australia, and Scandinavia: A behavioral-genetic analysis
Linköping University|University of New England|University of Colorado System|University of Colorado System|University of Colorado System|University of Colorado System|University of Colorado System|University of Colorado System
genetic environmental influences early reading spelling end kindergarten grade 1 compared across three twin samples tested united states australia scandinavia proportions variance due genetic influences kindergarten reading estimated 84 australia 68 us 33 scandinavia effects shared environment kindergarten reading estimated 09 australia 25 us 52 scandinavia similar pattern genetic environmental influences obtained kindergarten spelling one year later twins three samples received formal literacy instruction least one full school year heritability similarly high across country estimated genetic influences varying 79 83 reading 62 79 spelling findings indicate pattern genetic environmental influences early reading spelling development varies according educational context genetic influence increasing function increasing intensity early instruction longitudinal analyses revealed genetic continuity reading spelling kindergarten grade 1 across country however new genetic factor comes play accounting independent variance reading grade 1 us scandinavia suggesting change genetic influences reading implications responsetoinstruction discussed