autosomal recessive spinocerebellar ataxia 13
Findings
No curated finding names autosomal recessive spinocerebellar ataxia 13 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Autosomal recessive congenital cerebellar ataxia due to MGLUR1 deficiency is a rare, genetic, slowly progressive neurodegenerative disease resulting from MGLUR1 deficiency characterized by global developmental delay (beginning in infancy), mild to severe intellectual deficit with poor or absent speech, moderate to severe stance and gait ataxia, pyramidal signs (e.g. hyperreflexia) and mild dysdiadochokinesia, dysmetria, tremors, and/or dysarthria. Oculomotor signs, such as nystagmus, strabismus, ptosis and hypometric saccades, may also be associated. Brain imaging reveals progressive, generalized, moderate to severe cerebellar atrophy, inferior vermian hypoplasia, and/or constitutionally small brain.
Definition from the Mondo Disease Ontology (MONDO:0013905), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Infantile onset · Slowly progressive
HPO, annotations 2026-09-02
Features
34 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.
- Absent speechHPOHP:0001344
- 1 of 1 reported patient
- Occasional (5% to 29% of cases)
- AtaxiaHPOHP:0001251
- 1 of 1 reported patient
- Axial hypotoniaHPOHP:0008936
- 1 of 1 reported patient
- Cerebellar atrophyHPOHP:0001272
- 8 of 8 reported patients
- Delayed speech and language developmentHPOHP:0000750
- 10 of 10 reported patients
- DysarthriaHPO
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.
- GRM1HGNC:4593
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2023
- Strong · G2P · Autosomal recessive · 2015
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
8 names
Resolves to: autosomal recessive spinocerebellar ataxia 13
- Also called
- autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndrome caused by mutation in GRM1autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndrome caused by mutation in GRM1autosomal recessive congenital cerebellar ataxia due to metabotropic glutamate receptor 1 deficiencyautosomal recessive spinocerebellar ataxia type 13GRM1 autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndromeGRM1 autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndromeSCAR13spinocerebellar ataxia, autosomal recessive type 13