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ORPHA:101000

Autosomal recessive spastic paraplegia type 20

low confidenceDisorder

Also known as: Childhood-onset spastic paraparesis-distal muscle wasting syndrome · SPG20 · Troyer syndrome

Query health: suspect — Only one of 2 strategies returned hits (phrase).

Publications

1,304

Trials

0

Interventional, condition-specific

Researchers

1,253

Distinct authors in sample

Gene link

SPART

Definitive

Readiness

4/6

Stages with a signal

Clinical definition (Orphanet)

spastic paraplegia type 20 (SPG20) is a type of complex spastic paraplegia characterized by an onset in infancy of spastic paraparesis associated with distal amyotrophy, psuedobulbar palsy, motor and cognitive delays, mild cerebellar signs (dysarthria, dysdiadochokinesia, mild intention tremor), short stature and subtle skeletal abnormalities (pes cavus, mild talipes equinovarus, kyphoscoliosis). SPG20 is due to mutations in the SPG20 gene (13q13.1), which encodes the protein spartin.

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.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (3)

autosomal recessive spastic paraplegia type 20 · childhood-onset spastic paraparesis-distal muscle wasting syndrome · spastic paraplegia 20 (Troyer syndrome)

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

No matched interventional trial, but a gene association and an animal model are on record — often described as translation-ready / stalled at the clinical step.

  1. Gene identifiedPresent

    Definitive — SPART

  2. LiteraturePresent

    1,304 matched papers (873 in last 10 years) Source

  3. Phenotype characterisedPresent

    91 HPO annotations (e.g. Short foot; Distal amyotrophy; Flexion contracture) Source

  4. Animal modelPresent

    1 genotype model (Mus musculus) Source

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. 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?

Yes — we know a specific gene responsible (SPART).

GenCC classification: Definitive.

Phenotypes (Monarch / HPO)

91

Associated phenotypes · MONDO:0010156

  • Short foot
  • Distal amyotrophy
  • Flexion contracture
  • Spastic gait
  • Nystagmus

Showing 5 of 91 — open Monarch for the full list.

Animal models (Monarch / Alliance)

1

Model associations linked to this Mondo ID

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?

1,304

1,304 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.

1,304 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).

873 in the last 10 years · low confidence

Phrase hits: 665 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,253

Distinct author names in 200 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.

  1. 01
    Bakowska JC8 papers · 2015

    Cellular Neurology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 35, Room 2C-913, 9000 Rockville Pike, Bethesda, MD 20892-3704, USA.

    Papers in Europe PMC
  2. 02
    Blackstone C6 papers · 2012

    Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892

    Papers in Europe PMC
  3. 03
    Wang X6 papers · 2026

    Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA.

    Papers in Europe PMC
  4. 04
    Wang Y6 papers · 2026

    Metabolomics Shared Resource, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA.

    Papers in Europe PMC
  5. 05
    Bonora E4 papers · 2023

    Department of Medical and Surgical Sciences (DIMEC), St. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.

    Papers in Europe PMC
  6. 06
    Chen H4 papers · 2026

    Research Institute of the McGill University Health Centre 1001 boul Decarie Glen Site Block E Montreal, QC H4A 3J1 Canada

    Papers in Europe PMC
  7. 07
    Frazzi R4 papers · 2022

    Laboratory of Translational Research, Arcispedale S. Maria Nuova IRCCS, Viale Risorgimento 80, 42124 Reggio Emilia, Italy. Electronic address: raffaele.frazzi@asmn.re.it.

    Papers in Europe PMC
  8. 08
    Li Y4 papers · 2026

    Department of General Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Rd, Hangzhou 310016, China; Biomedical Research Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.

    Papers in Europe PMC
  9. 09
    Park J4 papers · 2023

    Department of Pharmacology, Chungnam National University School of Medicine, Daejeon 301-747, Republic of Korea.

    Papers in Europe PMC
  10. 10
    Zhang J4 papers · 2024

    School of Life Sciences, Henan University, Kaifeng 475004, China.

    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 11 September 2026 · last trial check 11 September 2026

No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.

low confidence · 38.6th 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.

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 spastic paraplegia type 20 — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This 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 20" OR "Childhood-onset spastic paraparesis-distal muscle wasting syndrome" OR "SPG20" OR "Troyer syndrome" OR "spastic paraplegia 20 (Troyer syndrome)") OR (MESH:"Spastic paraplegia 20, autosomal recessive") OR ("SPART" OR "SPART syndrome" OR "SPART-related")

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: Spastic paraplegia 20, autosomal recessive

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Autosomal recessive spastic paraplegia type 20" OR "Childhood-onset spastic paraparesis-distal muscle wasting syndrome" OR "SPG20" OR "Troyer syndrome" OR "spastic paraplegia 20 (Troyer syndrome)" OR "Spastic paraplegia 20, autosomal recessive"

Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: suspect — strategies attempted: phrase, mesh; 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
  • Publication count (1304) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-27T07:10:50.630Z