Using a Genetically Informative Longitudinal Design to Identify Homogeneous Subtypes of Language and Reading Impairment and Mechanisms Linking them to Social Maladjustment

Language and literacy impairments have been associated with poor social adjustment throughout development. Interestingly, Canadian researchers have been leaders in the study of these co-occurring problems, and have considerably documented their prevalence (Beitchman, Cohen, et al., 1996). Although the prevalence is well documented, we still know little about how this association develops. We propose to build on that Canadian expertise by evaluating mechanisms linking language and reading impairments to behaviour problems from infancy to the early school years. To do so we must first distinguish groups of children who share similar risk factors for language and literacy delays including genetic and/or environmental causes. This is especially important if we want to act on causes for prevention purposes. To consider both genetic and environmental risks, 1000 twins from the ongoing Quebec Newborn Twin Study will be assessed on language and reading related measures as well as multi-rater behavioural measures when they are in second grade. This is the first genetic study of language and literacy to include an important French-speaking sample which amounts to a crucial cross-linguistic contribution to this field of study. Twins and their parents have been followed at regular intervals since the twins were 5 months of age. We will look at stability and change of verbal development within the broad context of early development to expand our understanding of how early verbal delays are linked to social adjustment.

I don't have any books and nobody reads to me at home. I don't like school, except for recess. The longer I go without help, the more I will fall behind.

Effective reading instruction can overcome challenges at home. Early intervention and prevention are key.

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