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X-linked distal spinal muscular atrophy type 3

Disease definition

X-linked distal spinal muscular atrophy type 3 is a rare distal hereditary motor neuropathy characterized by slowly progressive atrophy and weakness of distal muscles of hands and feet with normal deep tendon reflexes or absent ankle reflexes and minimal or no sensory loss, sometimes mild proximal weakness in the legs and feet and hand deformities in males.


Classification level: Disorder
  • Synonym(s):
    • ATP7A-related distal motor neuropathy
    • DSMAX
    • SMAX3
    • X-linked dHMN3
    • X-linked dSMA3
    • X-linked distal hereditary motor neuropathy type 3
  • Prevalence: <1 / 1 000 000
  • Inheritance: X-linked recessive 
  • Age of onset: Adolescent, Adult, Infancy, Childhood
  • ICD-10: G12.2
  • OMIM: 300489
  • UMLS: C1845359
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

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