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Familial developmental dysphasia

Disease definition

Familial developmental dysphasia is a severe form of developmental verbal apraxia characterized by a deficit in spontaneous speech, writing, grammatical judgment and repetition, defective articulation, moderate to severe degree of dyspraxia, a reduced use of consonant clusters, and comprehension delay. Hearing and intelligence are normal.


Classification level: Disorder
  • Synonym(s):
    • Billard-Toutain-Maheut syndrome
    • FOXP2-associated dysphasia
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant 
  • Age of onset: Childhood
  • ICD-10: F80.1
  • OMIM: 600117
  • UMLS: C1838630
  • MeSH: -
  • GARD: 1823
  • MedDRA: -
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