The genetics of reading disabilities: from phenotypes to candidate genes.
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ABSTRACT:
SUBMITTER: Raskind WH
PROVIDER: S-EPMC3538356 | biostudies-literature | 2012
REPOSITORIES: biostudies-literature
Publications
The genetics of reading disabilities: from phenotypes to candidate genes.
Raskind Wendy H WH Peter Beate B Richards Todd T Eckert Mark M MM Berninger Virginia W VW
Frontiers in psychology 20130107
This article provides an overview of (a) issues in definition and diagnosis of specific reading disabilities at the behavioral level that may occur in different constellations of developmental and phenotypic profiles (patterns); (b) rapidly expanding research on genetic heterogeneity and gene candidates for dyslexia and other reading disabilities; (c) emerging research on gene-brain relationships; and (d) current understanding of epigenetic mechanisms whereby environmental events may alter behav ...[more]
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Project description:A number of candidate genes for reading and language impairment have been replicated, primarily in samples of children with developmental disability or delay, although these genes are also supported in adolescent population samples. The present study used a systematic approach to test 14 of these candidate genes for association with reading assessed in late adulthood (two cohorts with mean ages of 70 and 79 years). Gene-sets (14 candidates, axon-guidance and neuron migration pathways) and individual SNPs within each gene of interest were tested for association using imputed data referenced to the 1000 genomes European panel. Using the results from the genome-wide association (GWA) meta-analysis of the two cohorts (N?=?1217), a competitive gene-set analysis showed that the candidate gene-set was associated with the reading index (p?=?.016) at a family wise error rate corrected significance level. Neither axon guidance nor neuron migration pathways were significant. Whereas individual SNP associations within CYP19A1, DYX1C1, CNTNAP2 and DIP2A genes (p?<?.05) did not reach corrected significance their allelic effects were in the same direction as past available reports. These results suggest that reading skill in normal adults shares the same genetic substrate as reading in adolescents, and clinically disordered reading, and highlights the utility of adult samples to increase sample sizes in the genetic study of developmental disorders.
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