Disruptive Behavior, Global Developmental Delay, and Obesity in a 5-Year-Old Boy with a Chromosome Microduplication

Adam Braddock1, Miguel Del Campo2, Michael I Reiff3

  • 1Developmental Behavioral Pediatrics, Department of Pediatrics, University of California San Diego, Rady Children's Hospital, San Diego, CA.

Insights

A 5-year-old boy with developmental delay showed autism symptoms later in childhood. Genetic testing revealed a 2p25.3 microduplication, suggesting a potential cause for his autism diagnosis.

Area of Science:

  • Developmental Behavioral Pediatrics
  • Neurogenetics
  • Autism Spectrum Disorder Research

Background:

  • A 5-year-old boy presented with global developmental delay and disruptive behaviors.
  • Medical history included tethered spinal cord repair, exotropia, and severe obesity.
  • Initial assessments at 19 months showed no significant concerns for autism spectrum disorder.

Observation:

  • The child exhibited significant behavioral challenges: hyperactivity, aggression, tantrums, short attention span, and sleep difficulties.
  • Repetitive behaviors such as head rocking, stereotyped movements, and perseverative speech were noted.
  • Expressive language was severely limited, with only one-word utterances at age 5.

Findings:

  • Repeat psychological testing at age 5, including the Autism Diagnostic Observation Schedule-2 (ADOS-2), indicated autism with a high symptom severity.
  • Genetic analysis revealed a microduplication on chromosome 2p25.3, encompassing the myelin transcription factor 1-like (MYT1L) gene.
  • Fragile X testing was negative.

Implications:

  • This case highlights the potential for later-onset autism spectrum disorder diagnosis in children with developmental delays.
  • The identified 2p25.3 microduplication involving MYT1L may be a contributing genetic factor to the observed neurodevelopmental phenotype.
  • Further research into the role of MYT1L in neurodevelopment and autism is warranted.
Abstract

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