ORPHA:324262
Autosomal recessive congenital cerebellar ataxia due to MGLUR1 deficiency
Also known as: Autosomal recessive congenital cerebellar ataxia due to metabotropic glutamate receptor 1 deficiency · Autosomal recessive spinocerebellar ataxia type 13 · SCAR13
Query health: suspect — Source fetch failed for trials.
Publications
1,970
Trials
—
Interventional, condition-specific
Researchers
483
Distinct authors in sample
Gene link
GRM1
Strong
Readiness
4/6
Stages with a signal
Clinical definition (Orphanet)
A rare, genetic, slowly neurodegenerative disease resulting from MGLUR1 deficiency characterized by global (beginning in infancy), mild to severe intellectual deficit with poor or absent speech, moderate to severe stance and gait , 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 , generalized, moderate to severe cerebellar atrophy, inferior vermian hypoplasia, and/or constitutionally small brain.
How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0013905
- OMIM:614831
- UMLS:C3553816
Additional Mondo synonyms (8)
GRM1 autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndrome · GRM1 autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndrome · autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndrome caused by mutation in GRM1 · autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndrome caused by mutation in GRM1 · autosomal recessive congenital cerebellar ataxia due to metabotropic glutamate receptor 1 deficiency · autosomal recessive spinocerebellar ataxia 13 · autosomal recessive spinocerebellar ataxia type 13 · spinocerebellar ataxia, autosomal recessive type 13
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
4/6 stages with a signal
Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.
- Gene identifiedPresent
Strong — GRM1
- LiteraturePresent
1,970 matched papers (1,333 in last 10 years) Source
- Phenotype characterisedPresent
46 HPO annotations (e.g. Dysmetria; Seizure; Intellectual disability) Source
- Animal modelPresent
1 genotype model (Mus musculus) Source
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- Interventional trialNot checked
Trial fetch failed or incomplete
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Yes — we know a specific gene responsible (GRM1).
GenCC classification: Strong.
Phenotypes (Monarch / HPO)
46
Associated phenotypes · MONDO:0013905
- Dysmetria
- Seizure
- Intellectual disability
- Hyperreflexia
- Axial hypotonia
Showing 5 of 46 — open Monarch for the full list.
Animal models (Monarch / Alliance)
1
Model associations linked to this Mondo ID
- Grm1crv4/Grm1crv4 [background:] BALB/cPas-Grm1crv4·MGI:3664785·Mus musculus
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.
Open Targets candidates
No drugs or clinical candidates returned for this Mondo ID on Open Targets.
CTD chemicals (MyDisease.info)
No CTD chemical associations returned for this Mondo ID.
Literature
Is anyone studying this?
1,970
1,970 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
1,970 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
1,333 in the last 10 years · low confidence
Phrase hits: 66 · MeSH hits: 0
Who's working on it?
483
Distinct author names in 66 sampled papers — named people below.
Who's working on it?
People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.
- 01Wang Y5 papers · 2024
National Office for Maternal and Child Health Surveillance of China, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China.
Papers in Europe PMC - 02Liu Y3 papers · 2025
Department of Genetics, Jiangxi Maternal and Child Health Hospital, 330006, Nanchang, China.
Papers in Europe PMC - 03Zhang J3 papers · 2021
Cardiac Bioelectricity and Arrhythmia Center, Washington University, St. Louis, Missouri.
Papers in Europe PMC - 04
- 05Auburger G2 papers · 2025
Goethe University Frankfurt, University Hospital, Clinic of Neurology, Exp. Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany.
Papers in Europe PMC - 06Beaudin M2 papers · 2019
Axe Neurosciences, CHU de Québec-Université Laval, Québec, QC, Canada.
Papers in Europe PMC - 07Becker EBE2 papers · 2025
Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK. Electronic address: esther.becker@dpag.ox.ac.uk.
Papers in Europe PMC - 08Canet-Pons J2 papers · 2025
Goethe University Frankfurt, University Hospital, Clinic of Neurology, Exp. Neurology, Heinrich Hoffmann Str. 7, 60590 Frankfurt am Main, Germany.
Papers in Europe PMC - 09Gillies MC2 papers · 2024
Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
Papers in Europe PMC - 10Gregory KJ2 papers · 2024
Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
—
interventional trials for this specific condition
We could not load trial data for this condition right now.
Data as of 11 September 2026 · last trial check 31 July 2026
low confidence
Recruiting interventional trials
From the matched ClinicalTrials.gov set
Trial data could not be loaded for this build. This is not the same as finding zero interventional trials.
General rare disease registries you may be eligible for
These studies enroll across many rare conditions. They are not counted as evidence that anyone is studying this specific disease.
- NCT01793168·RECRUITING·Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford
Not reviewed·Conditions: Rare Disorders · Undiagnosed Disorders · Disorders of Unknown Prevalence · Cornelia De Lange Syndrome
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-30
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Autosomal recessive congenital cerebellar ataxia due to MGLUR1 deficiency — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
("Autosomal recessive congenital cerebellar ataxia due to MGLUR1 deficiency" OR "Autosomal recessive congenital cerebellar ataxia due to metabotropic glutamate receptor 1 deficiency" OR "Autosomal recessive spinocerebellar ataxia type 13" OR "SCAR13" OR "GRM1 autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndrome" OR "GRM1 autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndrome" OR "autosomal recessive cerebellar ataxia - pyramidal signs - nystagmus - oculomotor apraxia syndrome caused by mutation in GRM1" OR "autosomal recessive cerebellar ataxia-pyramidal signs-nystagmus-oculomotor apraxia syndrome caused by mutation in GRM1" OR "autosomal recessive spinocerebellar ataxia 13" OR "spinocerebellar ataxia, autosomal recessive type 13") OR ("GRM1" OR "GRM1 syndrome" OR "GRM1-related")ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Autosomal recessive congenital cerebellar ataxia due to MGLUR1 deficiency"
Query health: suspect — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Source errors: trials: Error: HTTP 400 for https://clinicaltrials.gov/api/v2/studies?query.cond=%22Autosomal%20recessive%20congenital%20cerebellar%20ataxia%20due%20to%20MGLUR1%20deficiency%22%20OR%20%22Autosomal%20recessive%20congenital%20cerebellar%20ataxia%20due%20to%20metabotropic%20glutamate%20receptor%201%20deficiency%22%20OR%20%22Autosomal%20recessive%20spinocerebellar%20ataxia%20type%2013%22%20OR%20%22SCAR13%22%20OR%20%22GRM1%20autosomal%20recessive%20cerebellar%20ataxia%20-%20pyramidal%20signs%20-%20nystagmus%20-%20oculomotor%20apraxia%20syndrome%22%20OR%20%22GRM1%20autosomal%20recessive%20cerebellar%20ataxia-pyramidal%20signs-nystagmus-oculomotor%20apraxia%20syndrome%22%20OR%20%22autosomal%20recessive%20cerebellar%20ataxia%20-%20pyramidal%20signs%20-%20nystagmus%20-%20oculomotor%20apraxia%20syndrome%20caused%20by%20mutation%20in%20GRM1%22%20OR%20%22autosomal%20recessive%20cerebellar%20ataxia-pyramidal%20signs-nystagmus-oculomotor%20apraxia%20syndrome%20caused%20by%20mutation%20in%20GRM1%22%20OR%20%22autosomal%20recessive%20spinocerebellar%20ataxia%2013%22%20OR%20%22spinocerebellar%20ataxia%2C%20autosomal%20recessive%20type%2013%22&format=json&pageSize=100&countTotal=true
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
- Publication count (1970) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity
Ingested 2026-07-27T13:34:13.674Z