ORPHA:9
Tetrasomy X syndrome
Also known as: 48,XXXX syndrome · Quadruple X · Tetra X
Publications
51
38.3th percentile
Trials
0
Interventional, condition-specific
Researchers
187
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
Tetrasomy X is a sex chromosome anomaly caused by the presence of two extra X chromosomes in females (48,XXXX instead of 46,XX).
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:0019525
- MeSH:C536502
- UMLS:C0265496
Additional Mondo synonyms (3)
quadruple X · tetra X · tetrasomy type X
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
51 matched papers (24 in last 10 years) Source
- Phenotype characterisedPresent
16 HPO annotations (e.g. Global developmental delay; Specific learning disability; Hip dysplasia) 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)
16
Associated phenotypes · MONDO:0019525
- Global developmental delay
- Specific learning disability
- Hip dysplasia
- Clinodactyly of the 5th finger
- Epicanthus
Showing 5 of 16 — 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?
51
51 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.
51 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).
24 in the last 10 years · medium confidence · 38.3th percentile (publications denominator)
Phrase hits: 51 · MeSH hits: 0
Who's working on it?
187
Distinct author names in 51 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.
- 01McCollough CH3 papers · 2020
Department of Radiology, Mayo Clinic, Rochester, MN, US.
Papers in Europe PMC - 02
- 03Bonezzi R2 papers · 2021
Institute for Physics, Humboldt University Berlin, Zum Großen Windkanal 6, D-12489 Berlin, Germany.
Papers in Europe PMC - 04Cardwell O2 papers · 2026
Department of Mathematics, University of Bonn, Bonn, 53115, Germany.
Papers in Europe PMC - 05Heitsch C2 papers · 2026
School of Mathematics, Georgia Institute of Technology, Atlanta, 30332, GA, USA. heitsch@math.gatech.edu.
Papers in Europe PMC - 06Hohm O2 papers · 2021
Institute for Physics, Humboldt University Berlin, Zum Großen Windkanal 6, D-12489 Berlin, Germany.
Papers in Europe PMC - 07
- 08Li Z2 papers · 2024
Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States.
Papers in Europe PMC - 09Liu J2 papers · 2024
School of Business, Anhui University, Hefei, Anhui 230601, China.
Papers in Europe PMC - 10Poznanović S2 papers · 2026
School of Mathematical and Statistical Sciences, Clemson University, Clemson, 29634, SC, USA.
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. 1 observational study did — shown below because natural-history and cohort work can be an important step toward a trial.
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.
Broader category tetrasomy also has no matched interventional trial. See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
Broader category: tetrasomy
0
Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.
Parent-category matching found a broader label but no interventional trials under it. How we count trials.
Observational and natural-history studies
1 observational study matches this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.
Recruiting or not-yet-recruiting
- NCT04463316·RECRUITING·GROWing Up With Rare GENEtic Syndromes
Conditions: Prader-Willi Syndrome · PWS-like Syndrome · Silver Russel Syndrome · Congenital Hypopituitarism·Matched via recall expansion
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 61 · after dedupe 61 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 61 · 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).
Uncertain / not reviewed (61)
- isrctn·ISRCTN12895613·No longer recruiting·Can the drug acipimox relieve muscle symptoms in patients with mitochondrial myopathy?
skipped — LLM skipped (--skip-llm)
- ctis·2025-524688-19-00·Authorised·A Phase III Randomized, Double-blind, Placebo-controlled Multicenter Master Protocol to Evaluate the Efficacy and Safety of Elecoglipron in Participants with Obesity or Overweight with or without Type 2 Diabetes Mellitus (Embold)
skipped — LLM skipped (--skip-llm)
- ctis·2025-524918-28-00·Authorised·A Randomized, Double-Blind, Placebo-Controlled Study to Investigate the Efficacy and Safety of SIR9900 in Patients with VEXAS Syndrome (SIVEX)
skipped — LLM skipped (--skip-llm)
- ctis·2025-523933-24-00·Authorised·A Randomized, Open-label, Parallel-group Phase III Study to Evaluate the Efficacy, Safety, and Tolerability of Elecoglipron Compared with Oral Semaglutide in Adults with Type 2 Diabetes Mellitus (Eluminate-2)
skipped — LLM skipped (--skip-llm)
- ctis·2026-526224-48-02·Authorised·Bioequivalence study of Vitamin D3 Pharma Patent 20,000 IU and the Vigantol 20,000 IU oral drops solutions and assessment of bioavailability in healthy volunteers
skipped — LLM skipped (--skip-llm)
- ctis·2026-525876-24-00·Authorised·Phase I/II clinical trial on the use of central nervous system administrations of CART-NKG2D or NKIL15 cells in children, adolescent and young adults with recurrent/refractory high grade Central Nervous System tumours (CINK-CAR)
skipped — LLM skipped (--skip-llm)
- ctis·2025-523725-17-00·Authorised·Inducing durable immunological control of HIV-1 through administration of long-acting broadly neutralizing antibodies and low-dose anti-PD-1 – a randomized, double-blinded, placebo-controlled trial (the IDUNN trial)
skipped — LLM skipped (--skip-llm)
- ctis·2026-526036-38-00·Authorised·Giving Upfront Anti-p40 to Reduce toxicity from Dual Immune Checkpoint Inhibition in MESOthelioma
skipped — LLM skipped (--skip-llm)
- ctis·2026-526581-24-01·Authorised·Oral versus Intravenous Tranexamic Acid for Blood Loss Prevention in Off-Pump Coronary Artery Bypass Surgery: A
Randomised Non-Inferiority Trial (TRANSCAB Study)
skipped — LLM skipped (--skip-llm)
- ctis·2025-523858-13-01·Authorised·High-dose Insulin Euglycemic Therapy in Non-Toxic Acute Cardiogenic Shock.
skipped — LLM skipped (--skip-llm)
- ctis·2025-523726-40-00·Authorised, ongoing·A PHASE III, OPEN-LABEL, SINGLE-ARM, MULTI-CENTER STUDY TO EVALUATE THE SAFETY AND USE OF AN ON-BODY DELIVERY SYSTEM FOR THE SUBCUTANEOUS HOME ADMINISTRATION OF OCRELIZUMAB IN PATIENTS WITH MULTIPLE SCLEROSIS
skipped — LLM skipped (--skip-llm)
- ctis·2026-526167-38-00·Authorised·ALBUMINUS: Dose reduction of human albumin during large-volume paracentesis in patients with cirrhosis
skipped — LLM skipped (--skip-llm)
- ctis·2026-526324-48-00·Authorised·Exploratory study of the performance of dynamic PET-CT acquisition to predict 6-month morphological response in patients with hepatocellular carcinoma treated with selective internal radiotherapy
skipped — LLM skipped (--skip-llm)
- ctis·2025-524879-23-00·Authorised·Epcoritamab in Relapsed/Refractory Marginalzone Lymphoma - A MULTICENTER OPEN LABEL SINGLE-ARM PHASE II STUDY (EPOS-1)
skipped — LLM skipped (--skip-llm)
- ctis·2025-522900-26-00·Authorised·Tacrolimus as prophylaxis of post-ERCP pancreatitis: a DPSG (Dutch Pancreatitis Study Group) multicenter, double-blind, randomized, placebo-controlled study.
skipped — LLM skipped (--skip-llm)
- ctis·2025-524640-35-00·Authorised·A Study to Evaluate the Long-term Safety and Efficacy of Long-acting Antibodies as Single Agents and in Combinations in Participants with Inflammatory Bowel Disease
skipped — LLM skipped (--skip-llm)
- ctis·2025-522176-86-01·Authorised·A Phase 2b/3, Randomized, Double-Blinded, Placebo Controlled Study ChecKing the Efficacy and Safety of ATAciguat to Slow the Progression of VaLvular DYsfunction in Participants with Moderate Calcific Aortic Valve STenosis
(KATALYST-AV)
skipped — LLM skipped (--skip-llm)
- ctis·2025-522301-37-00·Authorised, ongoing·A multicenter, randomized, double-blind, placebo-controlled, dose-ranging Phase IIb study to assess the efficacy and safety of GIA632 in adult participants with non-segmental vitiligo followed by an extension period
skipped — LLM skipped (--skip-llm)
- ctis·2026-525355-93-00·Authorised·PHASE III, OPEN-LABEL, RANDOMIZED, CONTROLLED, NON-INFERIORITY CLINICAL-TRIAL TO ASSESS THE EFFICACY AND SAFETY OF SHORT OUTPATIENT AMOXICILLIN REGIMENS IN CHILDREN WITH ACUTE STREPTOCOCCAL PHARYNGOTONSILLITIS (STOP – TRIAL)
skipped — LLM skipped (--skip-llm)
- ctis·2025-524363-20-01·Authorised·Phase II, Single-Center, Randomized, Double-Blind, Placebo-Controlled Clinical Trial To Evaluate The Safety And Efficacy Of Dasatinib To Reduce HIV-1 Reservoir, Chronic Inflammation, And Immune Senescence In People With HIV On Long-Term Antiretroviral Treatment.
skipped — LLM skipped (--skip-llm)
- ctis·2025-523675-39-00·Authorised, recruiting·A Phase 3, Randomized, Double-Blind, Placebo-Controlled, 3-Arm Study to Investigate the Safety and Efficacy of Efimosfermin Alfa in Participants With Biopsy-Confirmed F2- or F3-Stage Metabolic Dysfunction-Associated Steatohepatitis (MASH) (ZENITH-1)
skipped — LLM skipped (--skip-llm)
- ctis·2025-524741-28-00·Authorised·BIOlogical treatment GRAdual Interval Longing in severe Asthma (BIO-GRAIL)
skipped — LLM skipped (--skip-llm)
- ctis·2025-524395-30-00·Authorised·Discontinuation or Continuation of SGLT-2 Inhibitors Before Cardiac Surgery: Impact on Postoperative Cardiovascular Outcomes – DISCO Study
skipped — LLM skipped (--skip-llm)
- ctis·2025-523555-66-00·Authorised·A Phase 3, Randomized, Double-Blind, Active-Control Study of Pelabresib (DAK539) and Ruxolitinib vs. Placebo and Ruxolitinib in Adult Patients with Myelofibrosis who are JAK inhibitor naive
skipped — LLM skipped (--skip-llm)
- ctis·2024-516796-33-00·Authorised, ongoing·Efficacy of an anti-TSLP monoclonal antibody in the management of chronic bronchial disease induced by bronchiolitis obliterans syndrome in allogeneic hematopoietic stem cells transplantation recipients.
skipped — LLM skipped (--skip-llm)
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 Tetrasomy X 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.
("Tetrasomy X syndrome" OR "48,XXXX syndrome" OR "Quadruple X" OR "tetrasomy type X")ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Tetrasomy X syndrome" OR "48,XXXX syndrome" OR "Quadruple X" OR "tetrasomy type X" OR "Tetra X"
Recall-expansion terms: Tetra X
Study-type breakdown: 0 interventional · 1 observational · 0 expanded access. Only interventional studies enter the trial headline.
Parent-category trials query:
"tetrasomy"
Query health: ok — strategies attempted: phrase, recall-expansion; with hits: phrase, recall-expansion
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: Tetra X
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 2026-07-26T12:04:24.146Z