Clinical Characteristics

Note that the phenotypic spectrum of USP7 mutations is still being uncovered, and not all individuals with a HAFOUS present these features, but main characteristics include:

  • Developmental delay/intellectual disability
  • Autism spectrum disorder
  • Epilepsy
  • Abnormal brain MRI
  • Speech/motor impairments (some patients being completely non-verbal)
  • Neonatal hypotonia
  • Feeding problems
  • Joint contractures
  • Hypogonadism
  • Eye problems (strabismus, myopia, or nystagmus)
  • Short stature
  • Difficulty gaining weight
  • Gastrointestinal issues (reflux/GERD, chronic constipation, or chronic diarrhea)