Troyer syndrome
Findings
No curated finding names Troyer syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Autosomal recessive spastic paraplegia type 20 (SPG20) is a type of complex hereditary spastic paraplegia characterized by an onset in infancy of progressive spastic paraparesis associated with distal amyotrophy, psuedobulbar palsy, motor and cognitive delays, mild cerebellar signs (dysarthria, dysdiadochokinesia, mild intention tremor), short stature and subtle skeletal abnormalities (pes cavus, mild talipes equinovarus, kyphoscoliosis). SPG20 is due to mutations in the SPG20 gene (13q13.1), which encodes the protein spartin.
Definition from the Mondo Disease Ontology (MONDO:0010156), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Childhood onset
HPO, annotations 2026-09-02
Features
65 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Babinski signHPOHP:0003487
- 2 of 2 reported patients
- Frequent (30% to 79% of cases)
- Chronic constipationHPOHP:0012450
- 2 of 2 reported patients
- Distal amyotrophyHPOHP:0003693
- 2 of 2 reported patients
- Occasional (5% to 29% of cases)
- DysarthriaHPOHP:0001260
- 2 of 2 reported patients
- Frequent (30% to 79% of cases)
- DysmetriaHPOHP:0001310
- 2 of 2 reported patients
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- SPARTHGNC:18514
- Definitive · ClinGen · Autosomal recessive · 2022
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
4 names
Resolves to: Troyer syndrome
- Also called
- autosomal recessive spastic paraplegia type 20childhood-onset spastic paraparesis-distal muscle wasting syndromespastic paraplegia 20 (Troyer syndrome)SPG20