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A case of autism and uniparental disomy of chromosome 1

Thomas H Wassink1, Molly Losh, Rebecca S Frantz

  • 1Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA. thomas-wassink@uiowa.edu

Human Genetics
|May 12, 2005
PubMed

Insights

Maternal uniparental disomy (UPD) of chromosome 1 was identified in a child with autism. This genetic finding may unmask recessive mutations contributing to autism spectrum disorder.

Area of Science:

  • Genetics
  • Neurodevelopmental Disorders
  • Autism Spectrum Disorder Research

Background:

  • Autism spectrum disorder (ASD) is a complex neurodevelopmental condition with a significant genetic component.
  • Understanding the genetic underpinnings of ASD is crucial for diagnosis and potential therapeutic strategies.

Observation:

  • A male child diagnosed with autism exhibited maternal uniparental disomy (UPD) of chromosome 1.
  • The child presented with core autism symptoms, including language impairment, social communication deficits, and repetitive behaviors, along with associated features like mild intellectual disability and hyperactivity.
  • The mother, who had a history of psychiatric illness, showed personality and social traits resembling autism.

Findings:

  • Genome-wide linkage analysis revealed non-Mendelian inheritance and UPD of chromosome 1 in the affected child.
  • Detailed genotyping demonstrated alternating regions of heterodisomy and isodisomy on chromosome 1.
  • One region of isodisomy overlaps a known region of interest for autism on chromosome 1 (150-160 Mb).

Implications:

  • Maternal UPD of chromosome 1 may contribute to autism by unmasking recessive disease-causing mutations.
  • This finding highlights the role of uniparental disomy in neurodevelopmental disorders.
  • Further research into chromosome 1 UPD and its interaction with recessive mutations could offer new insights into autism etiology.

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