Reading is a fundamental human capacity that recruits and tunes brain circuitry subserving several neurocognitive skills. Individual differences in reading-related skills are largely influenced by genetic variation. However, the molecular basis of the heritability of reading-related skills remains narrowly replicated. Genome-wide association…

Purpose: Multiple factors impact reading acquisition in individuals with reading disability, including genetic disorders such as Williams syndrome (WS). Despite a relative strength in oral language, individuals with WS usually have an intellectual disability and tend to display deficits in areas associated with reading. There is substantial…

Purpose: To assess strengths and weaknesses of the reading level (RL) match approach and its potential to generate insights regarding the cognitive foundations of reading ability and disability. Method: We applied RL-match design to a sample of 2nd-6th graders reading a consistent orthography, Russian, using an "extreme phenotype"…

Background: The phenotypic and genetic associations between decoding skills and ADHD dimensions have been documented but less is known about the association with reading comprehension. The aim of the study is to document the phenotypic and genetic associations between reading comprehension and ADHD dimensions of inattention and…

The home literacy environment (HLE) predicts language and reading development in typically developing children; relatively little is known about its association with literacy development in children at family-risk of dyslexia. We assessed the HLE at age 4 years, precursor literacy skills at age 5, and literacy outcomes at age 6, in a sample of…

Although evidence suggests that individual differences in reading and mathematics skills are correlated, this relationship has typically only been studied in relation to word decoding or global measures of reading. It is unclear whether mathematics is differentially related to word decoding and reading comprehension. In the current study, the…

This study followed the development of reading speed, reading accuracy, and spelling in transparent Finnish orthography in children through Grades 2, 3, and 8. We compared 2 groups of children with familial risk for dyslexia--1 group with dyslexia (Dys _FR, n = 35) and 1 group without (NoDys_FR, n = 66) in Grade 2--with a group of children without…

Genetic and environmental relations between vocabulary and reading skills were explored longitudinally from preschool through Grades 2 and 4. At preschool there were strong shared-environment and weak genetic influences on both vocabulary and print knowledge but substantial differences in their source. Separation of etiology for vocabulary and…

As part of a longitudinal twin study of literacy and language, we conducted a behaviour-genetic analysis of orthographic learning, spelling and decoding in Grade 2 children (225 identical and 214 fraternal twin pairs) in the United States and Australia. Each variable showed significant genetic and unique environment influences. Multivariate…

The present study examined the effect of consanguineous marriage in the Arab community on reading disabilities of offspring. It examined whether the rate of reading disabilities was higher among offspring of first-cousin parents than offspring of unrelated parents; and whether reading-disabled children of first-cousin parents were more disabled in…