Preferred Label : Spinal muscular atrophy, type I;
Symbol : SMA1;
CISMeF acronym : SMA1;
Type : Phenotype, molecular basis known;
Alternative titles and symbols : Werdnig-hoffmann disease; Sma I; Sma, infantile acute form; Muscular atrophy, infantile;
Description : Spinal muscular atrophy refers to a group of autosomal recessive neuromuscular disorders
characterized by degeneration of the anterior horn cells of the spinal cord, leading
to symmetrical muscle weakness and atrophy. SMA is the second most common lethal,
autosomal recessive disease in Caucasians after cystic fibrosis (219700) (Wirth, 2000).
Four types of SMA are recognized depending on the age of onset, the maximum muscular
activity achieved, and survivorship: type I, severe infantile acute SMA, or Werdnig-Hoffman
disease; type II (253550), or infantile chronic SMA; type III (253400), juvenile SMA,
or Wohlfart-Kugelberg-Welander disease; and type IV (271150), or adult-onset SMA.
All types are caused by recessive mutations in the SMN1 gene. Lunn and Wang (2008)
provided a detailed review of clinical features, molecular pathogenesis, and therapeutic
strategies for SMA.;
Inheritance : Autosomal recessive;
Molecular basis : Caused by mutation in the survival of motor neuron 1 gene (SMN1, 600354.0001);
Prefixed ID : #253300;
Origin ID : 253300;
UMLS CUI : C5848259;
Automatic exact mappings (from CISMeF team)
Broader ORDO disease(s)
Currated CISMeF NLP mapping
DO Cross reference
Genes related to phenotype
HPO term(s)
ORDO concept(s)
Semantic type(s)
UMLS correspondences (same concept)