A family with a grand-maternally derived interstitial duplication of proximal 15q

Clin Genet. 2001 Dec;60(6):421-30. doi: 10.1034/j.1399-0004.2001.600604.x.


About 1% of individuals with autism or types of pervasive developmental disorder have a duplication of the 15q11-q13 region. These abnormalities can be detected by routine G-banded chromosome study, showing an extra marker chromosome, or demonstrated by fluorescence in situ hybridization (FISH) analysis, revealing an interstitial duplication. We report here the molecular, cytogenetic, clinical and neuropsychiatric evaluations of a family in whom 3 of 4 siblings inherited an interstitial duplication of 15q11-q13. This duplication was inherited from their mother who also had a maternally derived duplication. Affected family members had apraxia of speech, phonological awareness deficits, developmental language disorder, dyslexia, as well as limb apraxia but did not have any dysmorphic clinical features. The observations in this family suggest that the phenotypic manifestations of proximal 15q duplications may also involve language-based learning disabilities.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Apraxias / diagnosis
  • Apraxias / genetics
  • Child
  • Child, Preschool
  • Chromosome Disorders / diagnosis
  • Chromosome Disorders / genetics*
  • Chromosomes, Human, Pair 15*
  • Gene Duplication*
  • Genomic Imprinting
  • Humans
  • Language Development Disorders / diagnosis
  • Language Development Disorders / genetics
  • Learning Disabilities / diagnosis
  • Learning Disabilities / genetics
  • Male
  • Pedigree