ORPHA:320375
Autosomal recessive spastic paraplegia type 55
Also known as: SPG55
Publications
43
43.8th percentile
Trials
0
Interventional, condition-specific
Researchers
343
Distinct authors in sample
Gene link
—
Readiness
1/6
Stages with a signal
Clinical definition (Orphanet)
spastic paraplegia type 55 (SPG 55) is a rare, complex type of spastic paraplegia characterized by childhood onset of spastic paraplegia associated with optic atrophy (with reduced visual acuity and central scotoma), ophthalmoplegia, reduced upper-extremity strength and dexterity, muscular atrophy in the lower extremities, and sensorimotor . SPG55 is caused by mutations in the C12ORF65 gene (12q24.31) encoding probable peptide chain release factor C12orf65, .
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:0014020
- OMIM:615035
- UMLS:C3539506
Additional Mondo synonyms (2)
autosomal recessive spastic paraplegia type 55 · hereditary spastic paraplegia type 55
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.”
1/6 stages with a signal
Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
43 matched papers (30 in last 10 years) Source
- Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
- Animal modelNot checked
Not yet enriched from Monarch / Alliance
- Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
- Interventional trialNot found
No matched interventional trial under our ClinicalTrials.gov rules
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?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
Not enriched in this build — Monarch phenotype joins were not run for this record.
Animal models (Monarch / Alliance)
Not enriched in this build.
Literature
Is anyone studying this?
43
43 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.
43 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).
30 in the last 10 years · high confidence · 43.8th percentile (publications denominator)
Phrase hits: 43 · MeSH hits: 0
Who's working on it?
343
Distinct author names in 43 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Ishiura H3 papers · 2022
Department of Neurology, Graduate School of Medicine, The University of Tokyo, 113-8655 Tokyo, Japan. hishiura@yahoo.co.jp.
Papers in Europe PMC - 02Stevanin G3 papers · 2021
Department of Psychiatry (C.G.B., S.R., F.M.S.d.V., S.A.K.) and Department of Clinical Genetics (C.G.B., M.Q., G.J.B., H.B.B., V.B.), Erasmus MC, Rotterdam, The Netherlands; Sackler School of Medicine (Z.A., A.F.-V.), Tel-Aviv University, Ramat-Aviv; Pediatric Neurology Unit (A.F.-V.), Dana Children's Hospital, Tel-Aviv Medical Center, Israel; Department of Molecular Pharmacology (I.E.K., A.M.D.), Groningen Research Institute of Pharmacy, University of Groningen, The Netherlands; Clalit Health Services (R.M.), Sharon-Shomron, Hadera District; Faculty of Health Science (R.M.), Ben-Gurion University of the Negev, Beer Sheva; Metabolic Disease Unit (H.M.), Meyer Children's Hospital, Rambam Health Care Campus and Technion Faculty of Medicine, Haifa; Nursing Research Unit (M.A.T.), Soroka University Medical Center and Faculty of Health Science, Ben Gurion University of the Negev, Be'er Sheva, Israel; Ecole Pratique des Hautes Etudes (G.S.), PSL Research University, Neurogenetics Laboratory; Institut du Cerveau et de la Moelle Epinière (G.S., A.B.), Sorbonne University, Pierre and Marie Curie University UMR_S1127, INSERM u1127, CNRS UMR5225, Paris, France; Center for Biomics (W.F.J.v.I.), Erasmus MC; Department of Epidemiology (M.W.V.) and Department of Radiology (M.W.V.), Erasmus MC, Rotterdam, The Netherlands.
Papers in Europe PMC - 03Tsuji S3 papers · 2022
Department of Neurology, Graduate School of Medicine, The University of Tokyo, 113-8655 Tokyo, Japan. tsuji@m.u-tokyo.ac.jp.
Papers in Europe PMC - 04Abramov AY2 papers · 2016
UCL Institute of Neurology and MRC Centre for Neuromuscular Disease, Queen Square, London WC1N 3BG, UK.
Papers in Europe PMC - 05Boczonadi V2 papers · 2018
Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne NE1 3BZ, U.K.
Papers in Europe PMC - 06Brandner S2 papers · 2016
UCL Institute of Neurology and MRC Centre for Neuromuscular Disease, Queen Square, London WC1N 3BG, UK.
Papers in Europe PMC - 07Fratta P2 papers · 2016
UCL Institute of Neurology and MRC Centre for Neuromuscular Disease, Queen Square, London WC1N 3BG, UK.
Papers in Europe PMC - 08Higuchi Y2 papers · 2022
Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan.
Papers in Europe PMC - 09Horvath R2 papers · 2018
Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne NE1 3BZ, U.K. rita.horvath@ncl.ac.uk.
Papers in Europe PMC - 10Kumar KR2 papers · 2021
Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia. kkum4618@uni.sydney.edu.au.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).
Data as of 27 July 2026
No matched interventional trials. This is true for 73% of diseases in the trials denominator (5114 of 7003). Here are the researchers publishing on it.
high confidence · 36.5th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
Where to find support
We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:
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 spastic paraplegia type 55" OR "SPG55" OR "hereditary spastic paraplegia type 55"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Autosomal recessive spastic paraplegia type 55" OR "SPG55" OR "hereditary spastic paraplegia type 55"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-27T13:32:43.496Z