Orphanet: Proximal spinal muscular atrophy type 2

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Proximal spinal muscular atrophy type 2

Disease definition

Proximal spinal muscular atrophy type 2 (SMA2) is a chronic infantile form of proximal spinal muscular atrophy (see this term) characterized by 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):
    • Chronic infantile spinal muscular atrophy
    • Chronic spinal muscular atrophy
    • Intermediate spinal muscular atrophy
    • SMA type 2
    • SMA type II
    • SMA-II
    • SMA2
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: G12.1
  • OMIM: 253550
  • UMLS: C0393538  C2931358
  • MeSH: -
  • GARD: 4945
  • MedDRA: -

Detailed information

Article for general public


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