ORPHA:93338
Polysyndactyly
Also known as: PPD4 · Preaxial polydactyly type 4
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
1,019
Trials
1
Interventional, condition-specific
Researchers
1,339
Distinct authors in sample
Gene link
GLI3
Strong
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
Polysyndactyly or PPD4 is a form of preaxial polydactyly of fingers, a limb syndrome, characterized by the presence of a thumb showing the mildest degree of duplication, being broad, bifid or with radially deviated distal phalanx. Syndactyly of various degrees of third-and-fourth fingers is occasionally present.
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:0008272
- OMIM:174700
- UMLS:C1868111
Additional Mondo synonyms (3)
polydactyly, preaxial type 4 · polydactyly, preaxial, type IV · preaxial polydactyly type 4
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.”
3/6 stages with a signal
An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.
- Gene identifiedPresent
Strong — GLI3
- LiteraturePresent
1,019 matched papers (471 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 trialPresent
1 matched on ClinicalTrials.gov
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 (GLI3).
GenCC classification: Strong.
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?
1,019
1,019 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=5449) is 41.
1,019 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).
471 in the last 10 years · low confidence
Phrase hits: 1,019 · MeSH hits: 0
Who's working on it?
1,339
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.
- 01van Nieuwenhoven CA5 papers · 2022
Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Papers in Europe PMC - 02Ahmad W3 papers · 2025
Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Islamabad, Pakistan.
Papers in Europe PMC - 03Baas M3 papers · 2021
Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Papers in Europe PMC - 04Cai L3 papers · 2020
BGI-Guangzhou Medical Laboratory, BGI-Shenzhen, Guangzhou, China.
Papers in Europe PMC - 05de Klein A3 papers · 2022
Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Papers in Europe PMC - 06Galjaard RH3 papers · 2022
Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Papers in Europe PMC - 07Hovius SER3 papers · 2019
Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Papers in Europe PMC - 08Najmabadi H3 papers · 2024
Kariminejad - Najmabadi Pathology & Genetics Center, Tehran, Iran. hnajm12@yahoo.com.
Papers in Europe PMC - 09Potuijt JWP3 papers · 2022
Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands. j.potuijt@erasmusmc.nl.
Papers in Europe PMC - 10Ren J3 papers · 2020
Department of Health Management, School of Medicine, Hangzhou Normal University, No. 2318 Yuhangtang Road, Hangzhou, 311121, Zhejiang Province, China.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
1
interventional trials for this specific condition
1 interventional trial matched this specific condition name; none in our sample are currently recruiting.
Data as of 27 July 2026
1 interventional trial — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 76.8th percentile).
low confidence · 76.8th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
1 interventional trials matched after quoted-phrase search and title/condition post-filter.
No currently recruiting studies in the matched set. Open the same search on ClinicalTrials.gov.
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.
"Polysyndactyly" OR "Preaxial polydactyly type 4" OR "polydactyly, preaxial type 4" OR "polydactyly, preaxial, type IV"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Polysyndactyly" OR "Preaxial polydactyly type 4" OR "polydactyly, preaxial type 4" OR "polydactyly, preaxial, type IV" OR "GLI3"
Recall-expansion terms: GLI3
Interventional trials matched via: phrase (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 1 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, recall-expansion; with hits: phrase
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: PPD4
Confidence reasoning
- Preferred label is short or not clearly distinctive
- 1 synonym(s) dropped by stoplist (may under-count)
- "Polysyndactyly" also appears on ORPHA:93403
- Publication count (1019) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity
Ingested 2026-07-27T04:17:17.028Z