ORPHA:3307
Tetrasomy 18p syndrome
Also known as: Isochromosome 18p
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
177
58.8th percentile
Trials
0
Interventional, condition-specific
Researchers
953
Distinct authors in sample
Gene link
—
Readiness
1/6
Stages with a signal
Clinical definition (Orphanet)
Tetrasomy 18p is a very rare structural chromosomal anomaly affecting multiple body systems and characterized clinically by craniofacial abnormalities, delayed development, cognitive impairment, changes in muscle tone, distinctive facial features, and rarely renal malformations.
How rare: 1-9 / 1 000 000 — roughly one to nine people per million. In a city the size of Kolkata, perhaps a few dozen.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0013668
- MeSH:C538306
- OMIM:614290
- UMLS:C0795868
Additional Mondo synonyms (3)
tetrasomy 18p · tetrasomy type 18P · tetrasomy type 18p
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
177 matched papers (66 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?
177
177 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.
177 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).
66 in the last 10 years · high confidence · 58.8th percentile (publications denominator)
Phrase hits: 177 · MeSH hits: 0
Who's working on it?
953
Distinct author names in 177 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.
- 01Liehr T14 papers · 2025
Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, Jena D-07743, Germany ; Institut für Humangenetik, Postfach, Jena D-07740, Germany.
Papers in Europe PMC - 02Hale DE6 papers · 2019
The Chromosome 18 Registry and Research Society, San Antonio, TX, USA.
Papers in Europe PMC - 03Cody JD5 papers · 2019
Department of Pediatrics, Chromosome 18 Clinical Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
Papers in Europe PMC - 04Sebold C5 papers · 2018
Department of Pediatrics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
Papers in Europe PMC - 05Chen CP4 papers · 2020
Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan. Electronic address: cpc_mmh@yahoo.com.
Papers in Europe PMC - 06Eggermann T4 papers · 2000
Institute of Human Genetics, Technical University of Aachen, Germany.
Papers in Europe PMC - 07Hill A4 papers · 2019
Department of Pediatrics, Chromosome 18 Clinical Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
Papers in Europe PMC - 08Overhauser J4 papers · 1996
Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, USA.
Papers in Europe PMC - 09Soileau B4 papers · 2019
Department of Pediatrics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
Papers in Europe PMC - 10Wang W4 papers · 2017
Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Bioengineering, Tatung University, Taipei, Taiwan.
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.
"Tetrasomy 18p syndrome" OR "Isochromosome 18p" OR "tetrasomy 18p" OR "tetrasomy type 18P"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Tetrasomy 18p syndrome" OR "Isochromosome 18p" OR "tetrasomy 18p" OR "tetrasomy type 18P" OR "partial trisomy/tetrasomy of the short arm of chromosome 18" OR "partial trisomy/tetrasomy of chromosome 18"
Recall-expansion terms: partial trisomy/tetrasomy of the short arm of chromosome 18, partial trisomy/tetrasomy of chromosome 18
Study-type breakdown: 0 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
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 2026-07-26T22:49:02.568Z