Orphanet: Proximal spinal muscular atrophy type 1

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Proximal spinal muscular atrophy type 1

Disease definition

Proximal spinal muscular atrophy type 1 (SMA1) is a severe infantile form of proximal spinal muscular atrophy (see this term) characterized by severe and progressive muscle weakness and hypotonia resulting from the degeneration and loss of the lower motor neurons in the spinal cord and the brain stem nuclei.


Classification level: Subtype of disorder
  • Synonym(s):
    • Infantile spinal muscular atrophy
    • SMA type 1
    • SMA type I
    • SMA-I
    • SMA1
    • Werdnig-Hoffmann disease
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: G12.0
  • OMIM: 253300
  • UMLS: C0043116
  • MeSH: -
  • GARD: 7883
  • MedDRA: -

Detailed information

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