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ERIC Number: EJ971951
Record Type: Journal
Publication Date: 2012-Jun
Pages: 5
Abstractor: As Provided
ISSN: ISSN-1041-6080
Genetic and Environmental Etiologies of Reading Difficulties: DeFries-Fulker Analysis of Reading Performance Data from Twin Pairs and Their Non-Twin Siblings
Astrom, Raven L.; Wadsworth, Sally J.; Olson, Richard K.; Willcutt, Erik G.; DeFries, John C.
Learning and Individual Differences, v22 n3 p365-369 Jun 2012
Reading performance data from 254 pairs of identical (MZ) and 420 pairs of fraternal (DZ) twins, 8.0 to 20.0 years of age, were subjected to multiple regression analyses. An extension of the DeFries-Fulker (DF) analysis (DeFries & Fulker, 1985, 1988) that facilitated inclusion of data from 303 of their nontwin siblings was employed. In addition to providing estimates of heritability, this analysis yields a test of the difference between shared environmental influences for twins versus siblings (Astrom et al., 2011). Results suggest that proband reading deficits are due substantially to genetic factors (0.67 [plus or minus] 0.07, p less than 0.001), and that shared environmental influences are significantly higher for members of twin pairs than for those of twins and their nontwin siblings (viz., 0.25 versus 0.17, p = 0.02). (Contains 2 tables and 2 figures.)
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A