The Genetics of Autism Spectrum Disorders – A Guide for Clinicians

Faculty of Medicine, University of Heidelberg, Im Neuenheimer Feld 134b, 69120, Heidelberg, Germany, .
Current Psychiatry Reports (Impact Factor: 3.24). 01/2013; 15(1):334. DOI: 10.1007/s11920-012-0334-3
Source: PubMed


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.

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Available from: Christian P Schaaf
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    • "The most consistently reported single-gene disorders associated with ASD (*5% of cases) are Fragile X syndrome, Rett syndrome, tuberous sclerosis, and phosphatase and tensin homolog (PTEN) mutations (Carter and Scherer 2013). Rare genetic variants , and copy number variants in particular, have been shown to play a major role in ASD (Heil and Schaaf 2013). In addition to autism-related genes, various environmental events are thought to act as triggering factors in the development of ASD, including obstetric complications (Arndt et al. 2005; Libbey et al. 2005; Patterson 2009); prenatal influenza, rubella, and cytomegalovirus infections (Pardo et al. 2005); maternal stress during pregnancy (Beversdorf et al. 2005; but also see Rai et al. 2012); and maternal use of thalidomide (Strömland et al. 1994), misoprostol, and especially valproic acid during pregnancy (Landrigan 2010; Christensen et al. 2013). "
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