GRM1 encodes glutamate metabotropic receptor 1 (1,194 aa). G-protein coupled receptor for glutamate. Highest expression in Brain Cerebellar Hemisphere (38.3 TPM) and Brain Cerebellum (30.6 TPM).

Autosomal recessive spinocerebellar ataxia 13 is associated with mutations in the GRM1 gene on chromosome 6.

The GRM1 protein participates in L-Glutamate or L-Aspartate and 5' nucleotide bind umami taste receptor (TAS1R1:TAS1R3) and Sensory perception of taste pathways.

GRM1 is classified as a druggable target (Druggable Genome, G Protein Coupled Receptor, and Transporter categories) with score 2.2.

Genetic testing for GRM1 is available. Testing is considered confirmatory for diagnosis.

Phenotype severity distribution: 11 always present features, 4 very common features, 12 common features.

Estimated prevalence: <1 in 1,000,000 (VERY_RARE).

No clinical trials have been registered for autosomal recessive spinocerebellar ataxia 13.

3 publications have been identified in PubMed for autosomal recessive spinocerebellar ataxia 13. Research spans Case Report / Case Series (67%) and Review / Meta-Analysis (33%).

Recent Publications

• Ahmad S (2026). [PMID: 41649149](https://pubmed.ncbi.nlm.nih.gov/41649149/). *Clinical dysmorphology*. [Case Report / Case Series]

• Lan SC (2025). [PMID: 40199824](https://pubmed.ncbi.nlm.nih.gov/40199824/). *Cerebellum (London, England)*. [Review / Meta-Analysis]

• Ahmad R (2025). [PMID: 40858856](https://pubmed.ncbi.nlm.nih.gov/40858856/). *Cerebellum (London, England)*. [Case Report / Case Series]