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Current Psychiatry Reports

, 15:334 | Cite as

The Genetics of Autism Spectrum Disorders – A Guide for Clinicians

  • Karsten M. Heil
  • Christian P. SchaafEmail author
Genetic Disorders (JF Cubells and EB Binder, Section Editors)
Part of the following topical collections:
  1. Topical Collection on Genetic Disorders

Abstract

Recent advances in genetic testing technology have made chromosome microarray analysis (CMA) a first-tier clinical diagnostic test for Autism Spectrum Disorders (ASDs). Two main types of microarrays are available, single nucleotide polymorphism (SNP) arrays and array comparative genomic hybridization (aCGH), each with its own advantages and disadvantages in ASDs testing. Rare genetic variants, and copy number variants (CNVs) in particular, have been shown to play a major role in ASDs. More than 200 autism susceptibility genes have been identified to date, and complex patterns of inheritance, such as oligogenic heterozygosity, appear to contribute to the etiopathogenesis of ASDs. Incomplete penetrance and variable expressivity represent particular challenges in the interpretation of CMA testing of autistic individuals. This review aims to provide an overview of autism genetics for the practicing physician and gives hands-on advice on how to follow-up on abnormal CMA findings in individuals with neuropsychiatric disorders.

Keywords

Autism spectrum disorders ASDs Autism genetics Rare genetic variants Copy number variants CNVs Single-nucleotide polymorphisms arrays SNPs Chromosome microarrays Array comparative genomic hybridization aCGH Incomplete penetrance Variable expressivity Oligogenic heterozygosity Unclassified variants Synaptic plasticity Genome sequencing Common variant common disease model CVCV Rare variant common disease model RVCD Genetic disorders Psychiatry 

Notes

Acknowledgments

Dr. Schaaf ’s work is generously supported by the Joan and Stanford Alexander family and the Ting Tsung and Wei Fong Chao Foundation. Dr. Schaaf is the recipient of a Doris Duke Clinical Scientist Development Award.

Disclosure

K.M. Heil: none; C.P. Schaaf is a faculty member of the Department of Molecular and Human Genetics at Baylor College of Medicine, which derives revenue from chromosomal microarray analysis and whole exome sequencing offered in the Medical Genetics Laboratory.

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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  1. 1.Faculty of MedicineUniversity of HeidelbergHeidelbergGermany
  2. 2.Department of Molecular and Human GeneticsBaylor College of Medicine, Jan and Dan Duncan Neurological Research InstituteHoustonUSA

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