Home Page
Orphanet References OMIM Gene GeneReviews HGMD HGNC
last update : 22-01-2020
Symbol SPG20
Location 13q13.3
Name spastic paraplegia 20
Other name(s)
  • Troyer syndrome
  • spastic paraparesis childhood-onset with distal muscle wasting
  • Corresponding gene SPART
    Main clinical features
  • dysarthria, difficulty in learning to walk, progressive paraparesis primarily affecting lower limbs, distal amyotrophy, developmental delay and short stature
  • complicated spastic paraplegia associated with distal muscle wasting (Troyer syndrome)
  • Genetic determination autosomal recessive
    Function/system disorder neuromuscular
    Type disease
    Gene mutationChromosome rearrangementEffectComments
    deletion   abnormal protein/loss of function 1110delA mutation has lost mitochondrial localization
  • due to defective microtubule-mediated trafficking of mitochondria and/or mitochondrial dysfunction
  • impaired endocytosis may underlie the pathogenesis of Troyer syndrome (PMID: 17332501))
  • results from complete loss of spartin protein rather than from the predicted partly functional fragment which reflect increased protein degradation or impaired translation (PMID: 18413476))
  • mutant spartin containing the 1110delA mutation has lost mitochondrial localization (PMID: 16945107))