Machado-Joseph disease
Findings
No curated finding names Machado-Joseph disease yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease, is the most common subtype of type 1 autosomal dominant cerebellar ataxia (ADCA type 1), a neurodegenerative disorder, and is characterized by ataxia, external progressive ophthalmoplegia, and other neurological manifestations.
Definition from the Mondo Disease Ontology (MONDO:0007182), read 2026-09-29. CC BY 4.0.
- Onset and course
- Progressive · Late young adult onset
HPO, annotations 2026-09-02
Features
22 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.
- AtaxiaHPOHP:0001251
- 57 of 57 reported patients
- Abnormal pyramidal signHPOHP:0007256
- Very frequent (80% to 99% of cases)
- Abnormality of extrapyramidal motor functionHPOHP:0002071
- Very frequent (80% to 99% of cases)
- ClumsinessHPOHP:0002312
- Very frequent (80% to 99% of cases)
- Delayed speech and language developmentHPOHP:0000750
- Very frequent (80% to 99% of cases)
- DiplopiaHPOHP:0000651
- Very frequent (80% to 99% of cases)
Show the remaining 10
- ProptosisHPOHP:0000520
- Very frequent (80% to 99% of cases)
- Skeletal muscle atrophyHPOHP:0003202
- Very frequent (80% to 99% of cases)
- Gaze-evoked nystagmusHPOHP:0000640
- 15 of 20 reported patients
- External ophthalmoplegiaHPOHP:0000544
- 34 of 57 reported patients
- SpasticityHPOHP:0001257
- 62 of 139 reported patients
- Abnormal vestibular functionHPOHP:0001751
- Occasional (5% to 29% of cases)
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.
- ATXN3HGNC:7106
- Definitive · Laboratory for Molecular Medicine · Autosomal dominant · 2020
- Strong · Ambry Genetics · Autosomal dominant · 2018
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2021
Where it sits
Other names
8 names
Resolves to: Machado-Joseph disease
- Also called
- autosomal dominant striatonigral degenerationAzorean disease of the nervous systemMachado diseaseMJDNigro-spino-dentatal degeneration with nuclear ophthalmoplegiaSCA3spinocerebellar ataxia 3spinocerebellar ataxia type 3