Unraveling genetic and environmental components of early literacy: A twin study

Abstract

Even though the acquisition of early literacy skills obviously depends on stimuli and incentives in children's environment we may expect that genes define the constraints for acquiring some or all early literacy skills. Therefore behavior genetic analyses were carried out on twin data including 27 identical and 39 same sex dizygotic twins, 4 years old. We focused on a series of early literacy skills selected because they are developing in the focal age range: writing the proper name and mama, rhyming, and alphabetic knowledge. The data for each skill were subjected to structural equation modeling. First, it turned out that even in this young group genetic differences are the primary force in shaping early developing writing skills. Second, bivariate analyses showed that similar environmental and genetic influences are involved across various skills. Third, from secondary analyses on the available twin studies on early literacy it was apparent that the findings of this small-scaled study correspond to outcomes of other large-scale twin studies. © 2007 Springer Science+Business Media B.V.