Genetic and Environmental Influences on Literacy and Numeracy Performance in Australian School Children in Grades 3, 5, 7, and 9.
We examined the extent to which genes and the environment contributed to variation in and covariation among reading, spelling, grammar and punctuation, writing, and numeracy in Australian school children in Grades 3, 5, 7, and 9. Heritability was generally high: reading .58-.71 (excepting Grade 5 girls), spelling .68-.78; grammar and punctuation .52-.66, writing .39-.52, and numeracy .39-.79. Boys' performance varied more than girls in spelling and numeracy, and the common environment was a greater influence in girls than boys in Grade 3 numeracy and Grade 5 reading. Independent pathway models showed similar genetic and environmental structures at each grade with approximately one third to one half of the variation in each domain due to genes that influenced all domains. The covariation among the domains was largely mediated by genes. Results suggest substantial uniformity in the environmental factors influencing these academic domains.
Discipline of Psychology, School of Behavioural, Cognitive and Social Sciences, University of New England, Armidale, NSW, Australia. kgrasby2@une.edu.au.|Australian Research Council Centre of Excellence for Cognition and its Disorders, Sydney, NSW, Australia. kgrasby2@une.edu.au.|Queensland Institute of Medical Research, 300 Herston Rd, Herston, Brisbane, QLD, Australia. kgrasby2@une.edu.au.
Katrina L
KL
Grasby
Discipline of Psychology, School of Behavioural, Cognitive and Social Sciences, University of New England, Armidale, NSW, Australia.
William L
WL
Coventry
Discipline of Psychology, School of Behavioural, Cognitive and Social Sciences, University of New England, Armidale, NSW, Australia.|Australian Research Council Centre of Excellence for Cognition and its Disorders, Sydney, NSW, Australia.|National Health and Medical Research Council Centre of Excellence in Twin Research, Canberra, ACT, Australia.
Brian
B
Byrne
Department of Psychology, University of Colorado, Boulder, CO, USA.
Richard K
RK
Olson
Queensland Institute of Medical Research, 300 Herston Rd, Herston, Brisbane, QLD, Australia.
Sarah E
SE
Medland
D000293:Adolescent; D001315:Australia; D002648:Child; D005260:Female; D059647:Gene-Environment Interaction; D006801:Humans; D000067010:Literacy; D008297:Male; D015233:Models, Statistical; D015999:Multivariate Analysis; D010641:Phenotype; D011932:Reading; D012574:Schools
Academic achievement; Generalist genes; Numeracy; Reading; Sex differences; Twins