Molecular Genetics of Dyslexia


Dyslexia is a specific impairment in learning to read which affects 5–10% of school‐age children. Family and twin studies have shown that dyslexia is caused in large part by genetic factors. Dyslexia is most likely the result of the interplay of multiple genetic and environmental factors. Recently, several genes have been proposed as candidates for dyslexia susceptibility, including DYX1C1 on chromosome 15, KIAA0319 and DCDC2 on chromosome 6, ROBO1 on chromosome 3 and MRPL19 and C2ORF3 on chromosome 2. Interestingly, these genes share a putative role in brain development. No functional genetic variant has been identified for any of the genes but the study of their function offers for the first time new insights in the understanding of the biology of dyslexia and the mechanisms underlying cognition and brain function.

Key concepts

  • Several genes have recently been proposed as candidates for dyslexia susceptibility.

  • Most of these genes have shown association in independent samples of individuals with dyslexia.

  • A specific risk haplotype has been identified for the KIAA0319 gene.

  • Most of the candidates have been implicated in brain development.

  • No functional mutations have been identified for any of the genes.

  • Gene expression has been proposed as the main mechanism linking genetic susceptibility to the development of dyslexia

Keywords: reading; complex trait; association study; cognitive functions; neuronal migration

Figure 1.

Genomic location of dyslexia candidate genes. The location of the dyslexia candidates is shown in the context of the dyslexia susceptibility (DYX) loci identified through linkage studies and represented in the figure by red solid bars. The black arrows indicate the direction of transcription of the genes.



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Further Reading

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Ramus F (2004) Neurobiology of dyslexia: a reinterpretation of the data. Trends in Neurosciences 27: 720–726.

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How to Cite close
Paracchini, Silvia(Mar 2009) Molecular Genetics of Dyslexia. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0021474]