Autism pp 81-108 | Cite as

Autism in Genetic Intellectual Disability

Insights into Idiopathic Autism
  • Walter E. Kaufmann
  • George T. Capone
  • Megan Clarke
  • Dejan B. Budimirovic
Part of the Current Clinical Neurology book series (CCNEU)


Despite early controversy, it is currently accepted that a substantial proportion of children with intellectual disability of genetic origin meet criteria for autism spectrum disorders (ASD). This has led to an increased interest in studying conditions such as Fragile X syndrome (FXS) as genetic models of idiopathic ASD. Here, largely based on our own studies, we expand this notion to propose that the study of ASD in genetic intellectual disability can provide important clues about many aspects of idiopathic ASD including its core behavioral features. Thus, FXS could reveal a molecular–neurobiological–behavioral continuum for deficits in complex social interactions in ASD. Down syndrome (DS) could disclose similar bases for repetitive and stereotypic behaviors in ASD, while DS and Rett syndrome are likely to share commonly affected molecular–neurobiological–behavioral pathways with individuals with idiopathic ASD who experience developmental regression. Consequently, the in-depth characterization of ASD in genetic intellectual disability could be doubly rewarding by improving the clinical management of severely affected individuals with these disorders and by shedding light into key aspects of idiopathic ASD.


Autism genetics intellectual disability fragile X down Rett 


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Walter E. Kaufmann
    • 1
  • George T. Capone
  • Megan Clarke
  • Dejan B. Budimirovic
  1. 1.Kennedy Krieger InstituteBaltimoreUSA

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