Spinocerebellar ataxia type 20

Summary

Spinocerebellar ataxia type 20 (MONDO:0012098) is a disease and 1 clinical trial. A subtype of autosomal dominant cerebellar ataxia type I — broader associated-gene and molecular evidence is on the parent page (see Disease family below).

At a glance

• Prevalence: <1 / 1 000 000 (Worldwide) [Orphanet-validated]
• Phenotypes (HPO): 19
• Clinical trials: 1

Clinical features

Epidemiology

Prevalence records

2 prevalence record(s), Orphanet:

Type	Class	Value	Geography	Validation
Cases/families		20	Worldwide	Validated
Point prevalence	<1 / 1 000 000		Worldwide	Validated

Signs & symptoms

Clinical features (HPO)

19 HPO clinical features (Orphanet curated; top 19 by frequency):

HPO ID	Term	Frequency
HP:0001260	Dysarthria	Very frequent (80-99%)
HP:0001272	Cerebellar atrophy	Frequent (30-79%)
HP:0001618	Dysphonia	Frequent (30-79%)
HP:0002067	Bradykinesia	Frequent (30-79%)
HP:0002514	Cerebral calcification	Frequent (30-79%)
HP:0007338	Hypermetric saccades	Frequent (30-79%)
HP:0012049	Laryngeal dystonia	Frequent (30-79%)
HP:0030188	Tremor by anatomical site	Frequent (30-79%)
HP:0000640	Gaze-evoked nystagmus	Occasional (5-29%)
HP:0001251	Ataxia	Occasional (5-29%)
HP:0001347	Hyperreflexia	Occasional (5-29%)
HP:0002066	Gait ataxia	Occasional (5-29%)
HP:0002321	Vertigo	Occasional (5-29%)
HP:0007256	Abnormal pyramidal sign	Occasional (5-29%)
HP:0007351	Upper limb postural tremor	Occasional (5-29%)
HP:0010545	Downbeat nystagmus	Occasional (5-29%)
HP:0030185	Isometric tremor	Occasional (5-29%)
HP:0030186	Kinetic tremor	Occasional (5-29%)
HP:0002080	Intention tremor	Very rare (<1-4%)

Identifiers

Disease identifiers

Field	Value
Canonical name	spinocerebellar ataxia type 20
Mondo ID	MONDO:0012098
MeSH	C537199
OMIM	608687
Orphanet	101110
DOID	DOID:0050971
ICD-11	960716995
SNOMED CT	718771009
UMLS	C1837541
MedGen	373352
GARD	0009997
Is cancer (heuristic)	no

Also known as: SCA20 · spinocerebellar ataxia 20 · spinocerebellar ataxia type 20

Disease family

Classification path: disease › human disease › disease by etiologic mechanism › disease of genetic or genomic mechanism › hereditary disease › autosomal genetic disease › autosomal dominant disease › autosomal dominant cerebellar ataxia › autosomal dominant cerebellar ataxia type I › spinocerebellar ataxia type 20

Related subtypes (29): Machado-Joseph disease, spinocerebellar ataxia type 29, spinocerebellar ataxia type 34, spinocerebellar ataxia type 1, spinocerebellar ataxia type 2, spinocerebellar ataxia type 4, cerebellar ataxia-areflexia-pes cavus-optic atrophy-sensorineural hearing loss syndrome, autosomal dominant cerebellar ataxia, deafness and narcolepsy, spinocerebellar ataxia type 12, spinocerebellar ataxia type 13, spinocerebellar ataxia type 14, spinocerebellar ataxia type 15/16, spinocerebellar ataxia type 17, spinocerebellar ataxia type 19/22, spinocerebellar ataxia type 21, spinocerebellar ataxia type 18, spinocerebellar ataxia type 25, spinocerebellar ataxia type 8, spinocerebellar ataxia type 27, spinocerebellar ataxia type 23, spinocerebellar ataxia type 28, spinocerebellar ataxia type 35, spinocerebellar ataxia type 32, spinocerebellar ataxia type 36, cerebellar dysfunction with variable cognitive and behavioral abnormalities, spinocerebellar ataxia type 37, spinocerebellar ataxia type 40, spinocerebellar ataxia 46, neurodevelopmental disorder with motor abnormalities, seizures, and facial dysmorphism

Genetics & variants

GWAS landscape

No GWAS associations recorded — common-variant (GWAS) studies don’t cover this disease (typical for Mendelian / rare diseases). See the curated gene cohort and Mendelian overlap below.

Variant details and genetic-evidence tiers

No tiered GWAS variants or ClinVar records for this disease.

Genes & proteins

No associated-gene cohort resolved for this disease. Atlas builds the molecular and therapeutic sections — associated genes, protein families, druggability, pathways, interactions, and drug associations — by aggregating over a disease’s associated genes (resolved via GWAS / GenCC / ClinVar / CIViC), and none resolved here. This is expected for antibody-mediated, autoimmune, or otherwise non-gene-defined conditions; the curated evidence for this disease is its clinical features, GWAS susceptibility, and clinical trials (above).

Function

No pathway enrichment — requires an associated-gene cohort.

Therapeutics

No druggable-target or therapeutic data for this disease’s cohort.

Clinical trials & evidence

Clinical trials

Clinical trials: 1.

Phase distribution (across all retrieved trials)

Phase	Trials
Not specified	1

Top trials by phase / activity

NCT	Phase	Status	Title
NCT01793168	Not specified	RECRUITING	Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford