Caring for someone with this diagnosis? Eleplan keeps diagnoses, medications, documents and every specialist in one plan.
Start free with EleplanMachado-Joseph disease type 2
ORPHA:276241Clinical subtype
Also called SCA3, Thomas type · Spinocerebellar ataxia, Thomas type
What it is
Machado-Joseph disease type 2 is a subtype of Machado-Joseph disease (SCA3/MJD) with intermediate severity characterized by an intermediate age of onset, cerebellar ataxia and external progressive ophthalmoplegia, with variable pyramidal and extrapyramidal signs.
Key facts
- Age of onset
- Adult
- Inheritance
- Autosomal dominant
- Classified as
- Clinical subtype
Recorded for the broader condition
- Prevalence
- 1-9 / 100 000Spinocerebellar ataxia type 3
Orphanet records these for the broader condition rather than for this specific form. They are a starting point, not a figure for this subtype — subtypes often differ, and some are defined by being rarer than the condition they sit under.
Signs and symptoms
Very common80–99%
3- Abnormality of extrapyramidal motor functionDiagnostic criterion
- Progressive cerebellar ataxiaDiagnostic criterion
- Progressive external ophthalmoplegiaDiagnostic criterion
Common30–79%
22- Abnormal pyramidal sign
- Babinski sign
- Cerebellar atrophy
- Clumsiness
- Degeneration of the striatum
- Delayed speech and language development
- Dilated fourth ventricle
- Diplopia
- Dysarthria
- Dystonia
- Facial-lingual fasciculations
- Gaze-evoked nystagmus
- Hyperreflexia
- Peripheral neuropathy
- Progressive gait ataxia
- Proptosis
- Skeletal muscle atrophy
- Spasticity
- Spinocerebellar tract degeneration
- Substantia nigra gliosis
- Supranuclear ophthalmoplegia
- Upper motor neuron dysfunction
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
Powered by Eleplan
A rare diagnosis is just the start. Eleplan keeps the whole care plan in one place.
Diagnoses, medications, documents, appointments, and the whole care team — organized and always in sync, so you are not retelling the same story to every new specialist. With Ellie, your AI care assistant, on top of it. Free to start.