Features include always present findings: Saccadic smooth pursuit interruptions, Lower limb spasticity, Damage to the optic nerve (optic atrophy), and Brisk reflexes; and very common findings: Babinski sign. 20 total HPO annotations.

RNF170 function has not been fully characterized.

Spastic paraplegia 85, autosomal recessive is associated with mutations in the RNF170 gene on chromosome 8.

Genetic testing for RNF170 is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for spastic paraplegia 85, autosomal recessive has been reported in the published literature.

Phenotype severity distribution: 4 always present features, 1 very common feature, 4 common features.

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

No clinical trials have been registered for spastic paraplegia 85, autosomal recessive.

6 publications have been identified in PubMed for spastic paraplegia 85, autosomal recessive. Research spans Review / Meta-Analysis (50%), Diagnostic / Biomarker (17%), and Case Report / Case Series (17%).

Recent Publications

• Jeon YJ (2026). [PMID: 41486281](https://pubmed.ncbi.nlm.nih.gov/41486281/). *Signal transduction and targeted therapy*. [Review / Meta-Analysis]

• Agianda HAP (2026). [PMID: 41365832](https://pubmed.ncbi.nlm.nih.gov/41365832/). *Movement disorders : official journal of the Movement Disorder Society*. [Diagnostic / Biomarker]

• Erkan DD (2025). [PMID: 40827465](https://pubmed.ncbi.nlm.nih.gov/40827465/). *International journal of developmental neuroscience : the official journal of the International Society for Developmental Neuroscience*. [Review / Meta-Analysis]

• Haddad S (2025). [PMID: 39924761](https://pubmed.ncbi.nlm.nih.gov/39924761/). *European journal of neurology*. [Case Report / Case Series]