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Autism: the quest for the genes

Published online by Cambridge University Press:  03 September 2007

Nuala H. Sykes
Affiliation:
Wellcome Trust Centre for Human Genetics, University of Oxford, UK.
Janine A. Lamb*
Affiliation:
Centre for Integrated Genomic Medical Research, The University of Manchester, UK.
*
*Corresponding author: Janine A. Lamb, Centre for Integrated Genomic Medical Research (CIGMR), Stopford Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. Tel: +44 (0)161 275 1619; Fax: +44 (0)161 275 1617; E-mail: janine.lamb@manchester.ac.uk

Abstract

Autism, at its most extreme, is a severe neurodevelopmental disorder, and recent studies have indicated that autism spectrum disorders are considerably more common than previously supposed. However, although one of the most heritable neuropsychiatric syndromes, autism has so far eluded attempts to discover its genetic origins in the majority of cases. Several whole-genome scans for autism-susceptibility loci have identified specific chromosomal regions, but the results have been inconclusive and fine mapping and association studies have failed to identify the underlying genes. Recent advances in knowledge from the Human Genome and HapMap Projects, and progress in technology and bioinformatic resources, have aided study design and made data generation more efficient and cost-effective. Broadening horizons about the landscape of structural genetic variation and the field of epigenetics are indicating new possible mechanisms underlying autism aetiology, while endophenotypes are being used in an attempt to break down the complexity of the syndrome and refine genetic data. Although the genetic variants underlying idiopathic autism have proven elusive so far, the future for this field looks promising.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2007

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Further reading, resources and contacts

The University of California Santa Cruz Genome Browser allows access to the annotated reference human genome sequence as well as a large collection of other genomes, together with information on genes and gene expression, genetic variation and comparative genomics:

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