ORPHA:99776
Mosaic trisomy 9 syndrome
Also known as: Mosaic trisomy chromosome 9 · Trisomy 9 mosaicism
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
100
46.9th percentile
Trials
0
Interventional, condition-specific
Researchers
539
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
Mosaic trisomy 9 is a rare chromosomal anomaly syndrome, with a highly variable , principally characterized by , growth and , facial dysmorphism (incl. microphthalmia, deep-set eyes, low-set, malformed ears, bulbous nose, high-arched palate, micrognathia) and heart defects (e.g. ventricular septal defect), as well as urogenital (e.g. hypoplastic genitalia, cryptorchidism), skeletal ( joint dislocations or hyperflexion, scoliosis/kyphosis) and central nervous system anomalies (hydrocephalus, Dandy-Walker ). Pigmentary mosaic skin lesions along the lines of Blaschko are also frequently observed.
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:0020490
- MeSH:C535454
- UMLS:C2930908
Additional Mondo synonyms (1)
Mosaic trisomy type 9
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
No specific-condition interventional trial, but broader-category trials exist — discuss eligibility with a clinician.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
100 matched papers (35 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 trialPartial
None under the specific name; 20 for broader category trisomy
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?
100
100 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.
100 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).
35 in the last 10 years · high confidence · 46.9th percentile (publications denominator)
Phrase hits: 100 · MeSH hits: 0
Who's working on it?
539
Distinct author names in 100 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.
- 01Li H4 papers · 2025
Genetic Medical Center, Women and Children's Health Care Hospital of Linyi, Liyin, 276014, China.
Papers in Europe PMC - 02Wang Y4 papers · 2025
The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Papers in Europe PMC - 03Chen Y3 papers · 2025
The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Papers in Europe PMC - 04Sánchez JM3 papers · 1986Papers in Europe PMC
- 05Yong SL3 papers · 2014
Department of Medical Genetics, UBC, Vancouver, British Columbia, Canada.
Papers in Europe PMC - 06Arbour L2 papers · 2009Papers in Europe PMC
- 07Armstrong L2 papers · 2009Papers in Europe PMC
- 08Baross A2 papers · 2009Papers in Europe PMC
- 09Bianchi DW2 papers · 2011Papers in Europe PMC
- 10Birch P2 papers · 2009Papers 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). 20 trials are registered for trisomy, the broader category — shown separately because they may or may not enrol this specific subtype.
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.
20 interventional trials matched trisomy, the broader category — listed below. Those studies are not counted in the condition-specific total.
Broader category: trisomy
20
Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.
Worth raising with a clinician. How we count trials.
Recruiting under the broader category
- NCT05231798·RECRUITING·Cholinergic Integrity in Down Syndrome in Association With Aging, Alzheimer's Disease Pathology, and Cognition
Conditions: Down Syndrome · Down Syndrome, Partial Trisomy 21 · Alzheimer Disease·Matched via name phrase
- NCT06911944·NOT YET RECRUITING·Amyloid Lowering for Alzheimer's in Down's With Donanemab Investigation
Conditions: Down Syndrome (DS) · Down Syndrome (Trisomy 21) · Alzheimer Disease · Amyloid Beta Protein·Matched via name phrase
- NCT07658053·NOT YET RECRUITING·Effects of a Pacifier on Obstructive Sleep Apnea and Its Repercussions in Infants With Down Syndrome
Conditions: Obstructive Sleep Apnea · Down Syndrome (Trisomy 21)·Matched via name phrase
- NCT07234695·RECRUITING·LEvetiracetam to Prevent Seizures in Symptomatic Alzheimer's Disease in Adults With Down Syndrome
Conditions: Down Syndrome · Down Syndrome (DS) · Down Syndrome (Trisomy 21) · Alzheimer Dementia·Matched via name phrase
- NCT06938542·ENROLLING BY INVITATION·Palliative Care Needs of Children With Rare Diseases and Their Families
Conditions: Trisomy 13 Syndrome · Arthrogryposis Congenita Multiplex With Intestinal Atresia · Asparagine Synthetase Deficiency · CHARGE Syndrome·Matched via name phrase
- NCT05527652·RECRUITING·Self-Supporting Nasopharyngeal Airway (ssNPA) Treating Upper Airway Obstruction in Hypotonia
Conditions: Obstructive Sleep Apnea · Hypertonia, Muscle · Nasal Airway Obstruction · Tolerance·Matched via name phrase
- NCT05970965·RECRUITING·Periodontitis and Inflammation in Children With Down Syndrome/Trisomy 21: Study on Biological Samples
Conditions: Periodontitis · Trisomy 21·Matched via name phrase
- NCT06783725·RECRUITING·Sleep Intervention and Quality of Life in Down Syndrome
Conditions: Down Syndrome · Down Syndrome (Trisomy 21)·Matched via name phrase
- NCT07334912·RECRUITING·AEF0217 in Participants With Down Syndrome
Conditions: Down Syndrome (Trisomy 21)·Matched via name phrase
- NCT06740162·RECRUITING·Physical Activity and Community EmPOWERment Project
Conditions: Intellectual Disability · Neurodevelopmental Disorders · Autism Spectrum Disorder · Down Syndrome·Matched via name phrase
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.
"Mosaic trisomy 9 syndrome" OR "Mosaic trisomy chromosome 9" OR "Trisomy 9 mosaicism" OR "Mosaic trisomy type 9"
MeSH descriptor terms unioned into the query: Chromosome 9, trisomy mosaic
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Mosaic trisomy 9 syndrome" OR "Mosaic trisomy chromosome 9" OR "Trisomy 9 mosaicism" OR "Mosaic trisomy type 9" OR "Chromosome 9, trisomy mosaic"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Parent-category trials query:
"trisomy"
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
Ingested 2026-07-27T06:16:50.619Z