Molecular Genetics of Autism

Janine A Lamb, University of Manchester, Manchester, UK

Published online: March 2009

DOI: 10.1002/9780470015902.a0021455

Autism is a behaviourally defined lifelong neurodevelopmental disorder, with strong evidence for a complex genetic predisposition. Extensive genetic research has been carried out over the last decade using cytogenetic, linkage and association approaches to identify the underlying risk variants, with generally equivocal results. The most exciting recent finding to emerge in autism genetics is the discovery of submicrosopic copy number variants and rare gene mutations that appear to increase the risk of autism. These findings suggest possible biological pathways involved, pointing to postsynaptic density genes and defective glutamatergic synaptogenesis. Some of these variants are also implicated in mental retardation and other neurodevelopmental and psychiatric disorders. Together, these findings suggest considerable genetic and clinical heterogeneity underlies autism spectrum disorders, and that convergent approaches may be required to identify risk alleles.

Key concepts

  • Autism is a behaviourally defined lifelong neurodevelopmental disorder, with strong evidence for a complex genetic predisposition.
  • A large number of linkage and candidate gene association studies carried out over the last decade to identify risk variants have yielded generally equivocal results.
  • Submicrosopic copy number variants and rare gene mutations have recently been discovered that appear to increase the risk of autism; the same variants may also influence mental retardation and other neurodevelopmental and psychiatric disorders.
  • These findings implicate postsynaptic density genes and defective glutamatergic synaptogenesis in susceptibility to autism.
  • There is increasing recognition that considerable genetic and clinical heterogeneity is likely to underlie autism spectrum disorders.
  • Interdisciplinary, convergent approaches and large sample sizes may be required to identify the risk variants and biological pathways involved.
  • Technologies are rapidly evolving together with knowledge of the human genome, providing greater ability to assay genetic variation.

Keywords: autism; linkage; association; copy number variation; heterogeneity

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Related Sub-Topics:

Receptors for Neurotransmitters | Neurobiology of Disease | Nervous System Development | Neural Networks and Behaviour | Postsynaptic Signalling Mechanisms | Molecular Genetics of Common and Complex Disease | Genetics of Intelligence and Cognition | Linkage Analysis | Gene Mapping by Disease Association
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Article Title: Molecular Genetics of Autism
 
How to Cite close
Lamb, Janine A(Mar 2009) Molecular Genetics of Autism. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0021455]