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Severe intellectual disability and progressive spastic paraplegia

Disease definition

A rare complex hereditary spastic paraplegia characterized by an early onset hypotonia that progresses to spasticity, global developmental delay, severe intellectual disability and speech impairment, microcephaly, short stature and dysmorphic features. Patients often become non-ambulatory, and some develop seizures and stereotypic laughter.


Classification level: Disorder
  • Synonym(s):
    • AP4 deficiency syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: G11.4
  • OMIM: 612936  613744  614066  614067
  • UMLS: C4755264
  • MeSH: -
  • GARD: 10999
  • MedDRA: -

Detailed information

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Disease review articles


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