ORPHA:1598
Monosomy 18p syndrome
Also known as: 18p- syndrome · De Grouchy syndrome type 1
Publications
268
55.6th percentile
Trials
0
Interventional, condition-specific
Researchers
1,122
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare deletion of all or part of the short arm of chromosome 18 characterized by a highly variable , most commonly including global , short stature, and facial features.
How rare: 1-9 / 100 000 — about one to nine people per hundred thousand.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0007800
- MeSH:C538309
- OMIM:146390
- UMLS:C0432442
- NCIT:C84521
Additional Mondo synonyms (11)
18p syndrome · 18p- · chromosome 18p deletion · chromosome 18p deletion syndrome · deletion 18p syndrome · monosomy type 18p · partial deletion of chromosome 18p · partial deletion of the short arm of chromosome 18 · partial deletion of the short arm of chromosome type 18 · partial monosomy of chromosome 18p · partial monosomy of the short arm of chromosome 18
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.”
2/6 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
268 matched papers (89 in last 10 years) Source
- Phenotype characterisedPresent
70 HPO annotations (e.g. Epicanthus; Toe syndactyly; Barrel-shaped chest) Source
- Animal modelNot found
No Alliance genotype “model of” associations via Monarch for these Mondo IDs
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- 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)
70
Associated phenotypes · MONDO:0007800
- Epicanthus
- Toe syndactyly
- Barrel-shaped chest
- Dystonia
- Short stature
Showing 5 of 70 — open Monarch for the full list.
Animal models (Monarch / Alliance)
None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.
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?
268
268 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=3967) is 59.
268 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).
89 in the last 10 years · medium confidence · 55.6th percentile (publications denominator)
Phrase hits: 268 · MeSH hits: 0
Who's working on it?
1,122
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.
- 01Liehr T11 papers · 2025
Department of Human Genetics, University Clinic, Jena, Germany.
Papers in Europe PMC - 02Cody JD4 papers · 2018
University of Texas Health Science Center at San Antonio, Chromosome 18 Research Center, San Antonio, Texas.
Papers in Europe PMC - 03He J3 papers · 2024
Department of Genetics and Eugenics, Changsha Hospital for Maternal & Child Health Care Affiliated to Hunan Normal University, Changsha, 410007, Hunan, China.
Papers in Europe PMC - 04Heard P3 papers · 2018
University of Texas Health Science Center at San Antonio, Chromosome 18 Research Center, San Antonio, Texas.
Papers in Europe PMC - 05Kankel S3 papers · 2025
Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Am Klinikum 1, 07747, Jena, Germany.
Papers in Europe PMC - 06Qin Y3 papers · 2026
Wuhan Medical Care Center for Women and Children, Wuhan, 430015, China.
Papers in Europe PMC - 07Weise A3 papers · 2023
Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, 07747 Jena, Germany.
Papers in Europe PMC - 08Wu J3 papers · 2026
Prenatal Diagnosis Centre, Guangdong Women and Children Hospital, Guangzhou, Guangdong 510010, China ; Maternal and Children Metabolic-Genetic Key Laboratory, Guangdong Women and Children Hospital, Guangzhou, Guangdong 510010, China.
Papers in Europe PMC - 09Yang Y3 papers · 2025
Prenatal Diagnosis Center, Hangzhou Maternity and Child Care Hospital, #369 Kunpeng Road, Shangcheng District, Hangzhou, 310008, Zhejiang, China.
Papers in Europe PMC - 10Zhang Y3 papers · 2021
Department of Clinical Genetics, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110003 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.
medium 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 2026-07-29
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 Monosomy 18p syndrome — check Associations / patient organisations on that page.
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.
"Monosomy 18p syndrome" OR "18p- syndrome" OR "De Grouchy syndrome type 1" OR "18p syndrome" OR "chromosome 18p deletion" OR "chromosome 18p deletion syndrome" OR "deletion 18p syndrome" OR "monosomy type 18p" OR "partial deletion of chromosome 18p" OR "partial deletion of the chromosome 18p" OR "partial deletion of the short arm of chromosome 18" OR "partial deletion of short arm of chromosome 18" OR "partial deletion of the short arm of chromosome type 18" OR "partial deletion of short arm of chromosome type 18" OR "partial monosomy of chromosome 18p" OR "partial monosomy of the chromosome 18p" OR "partial monosomy of the short arm of chromosome 18" OR "partial monosomy of short arm of chromosome 18"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Monosomy 18p syndrome" OR "18p- syndrome" OR "De Grouchy syndrome type 1" OR "18p syndrome" OR "chromosome 18p deletion" OR "chromosome 18p deletion syndrome" OR "deletion 18p syndrome" OR "monosomy type 18p" OR "partial deletion of chromosome 18p" OR "partial deletion of the chromosome 18p" OR "partial deletion of the short arm of chromosome 18" OR "partial deletion of short arm of chromosome 18" OR "partial deletion of the short arm of chromosome type 18" OR "partial deletion of short arm of chromosome type 18" OR "partial monosomy of chromosome 18p" OR "partial monosomy of the chromosome 18p" OR "partial monosomy of the short arm of chromosome 18" OR "partial monosomy of short arm of chromosome 18"
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
Synonyms dropped by stoplist: 18p-
Confidence reasoning
- Preferred label is multi-word and distinctive
- 1 synonym(s) dropped by stoplist (may under-count)
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-26T17:48:13.148Z