Kisho is an information platform, not a medical provider. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. All content is aggregated from publicly available sources (including ClinicalTrials.gov, PubMed, FDA.gov, and Orphanet) and is provided for informational purposes only. Clinical trial eligibility, treatment decisions, and any health-related actions should always be discussed with a qualified healthcare professional. Kisho does not endorse any specific therapy, organization, or clinical trial. Terms of use · Privacy policy
Pontocerebellar hypoplasia type 6 (PCH6) is a rare form of pontocerebellar hypoplasia characterized clinically at birth by hypotonia, clonus, epilepsy impaired swallowing and from infancy by progressive microencephaly, spasticity and lactic acidosis.
Data assembled from 6 of 12 sources · Last updated Sep 19, 2026, 9:41 PM UTC
Online Mendelian Inheritance in Man
European rare disease database
Genetic and Rare Diseases Info Center
Features include always present findings: Generalized hypotonia, Failure to thrive, Feeding difficulties, and Profound global developmental delay; and common findings: Lethargy, Cerebral cortical atrophy, Shrinkage of the cerebellum (cerebellar atrophy), and Gastroesophageal reflux and others. 38 total HPO annotations.
Organ System | Phenotype Count | Example Features |
|---|---|---|
Brain and nerves | 13 | Seizure, Cerebral cortical atrophy, Lower limb spasticity |
Muscles | 9 | Cerebral cortical atrophy, Shrinkage of the cerebellum (cerebellar atrophy), Low muscle tone (hypotonia) |
Lab test results | 4 | Decreased activity of mitochondrial complex III, Increased circulating lactate concentration, Decreased activity of mitochondrial complex I |
Head and neck | 3 | Narrow palate, Progressive microcephaly, Microcephaly |
Digestive system | 2 | Gastroesophageal reflux, Feeding difficulties |
Arms and legs | 2 | Lower limb spasticity, Upper limb spasticity |
Growth and development | 1 | Failure to thrive |
Lungs and breathing | 1 | Apnea |
RARS2 function has not been fully characterized.
Pontocerebellar hypoplasia type 6 is associated with mutations in the RARS2 gene on chromosome 6.
Genetic testing for RARS2 is available. Testing is considered confirmatory for diagnosis.
Phenotype severity distribution: 4 always present features, 20 common features.
Estimated prevalence: <1 in 1,000,000 (VERY_RARE).
No clinical trials have been registered for pontocerebellar hypoplasia type 6.
2 publications have been identified in PubMed for pontocerebellar hypoplasia type 6. Kisho has analyzed 1 by research type. Research spans Review / Meta-Analysis (100%).
Kukulka NA (2025). [PMID: 40936650](https://pubmed.ncbi.nlm.nih.gov/40936650/). *Brain Commun*. [Review / Meta-Analysis]