ORPHA:480907
X-linked intellectual disability-global development delay-facial dysmorphism-sacral caudal remnant syndrome
Query health: suspect — Only one of 2 strategies returned hits (phrase). Source fetch failed for trials.
Publications
20
37.1th percentile
Trials
—
Interventional, condition-specific
Researchers
224
Distinct authors in sample
Gene link
TAF1
Definitive
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare multiple anomalies/ syndrome characterized by global , , growth retardation, hearing impairment, characteristic facial dysmorphology (including prominent supraorbital ridges, downslanting palpebral fissures, deep-set eyes, long face, sagging cheeks, anteverted nares, and pointed chin), generalized , joint hypermobility, gluteal crease with sacral caudal remnant and sacral dimple, and variable neurological features. Various ophthalmic, cutaneous, musculoskeletal, gastrointestinal, and cardiovascular anomalies have also been described.
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:0018823
- MONDO:0010500
- OMIM:300966
- UMLS:C4225418
Additional Mondo synonyms (7)
MRXS33 · TAF1 X-linked syndromic intellectual disability · X-linked syndromic intellectual disability caused by mutation in TAF1 · intellectual developmental disorder, X-linked syndromic 33, X-linked recessive · intellectual disability, X-linked, syndromic type 33 · mental retardation, X-linked, syndromic 33 · mental retardation, X-linked, syndromic type 33
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 identifiedPresent
Definitive — TAF1
- LiteraturePresent
20 matched papers (20 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 checked
Trial fetch failed or incomplete
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 (TAF1).
GenCC classification: Definitive.
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?
20
20 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.
20 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).
20 in the last 10 years · high confidence · 37.1th percentile (publications denominator)
Phrase hits: 20 · MeSH hits: 0
Who's working on it?
224
Distinct author names in 20 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.
- 01Chen C3 papers · 2026
Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, China.
Papers in Europe PMC - 02Cleverley K3 papers · 2025
Department of Neuromuscular Diseases, UCL Institute of Neurology, University College London, London WC1N 3BG, UK.
Papers in Europe PMC - 03Crombie EM3 papers · 2025
Department of Neuromuscular Diseases, UCL Institute of Neurology, University College London, London WC1N 3BG, UK.
Papers in Europe PMC - 04Boinon L2 papers · 2020
Department of Pharmacology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA.
Papers in Europe PMC - 05Fisher EMC2 papers · 2024
Department of Neuromuscular Diseases, UCL Institute of Neurology, University College London, London WC1N 3BG, UK.
Papers in Europe PMC - 06Janakiraman U2 papers · 2020
Department of Pathology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA.
Papers in Europe PMC - 07Khanna R2 papers · 2020
Department of Pathology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA; Department of Pharmacology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA; The Center for Innovation in Brain Sciences, The University of Arizona Health Sciences, Tucson, AZ, United States of America; The BIO5 Institute, University of Arizona, United States of America.
Papers in Europe PMC - 08Lupski JR2 papers · 2022
Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.
Papers in Europe PMC - 09Moutal A2 papers · 2020
Department of Pharmacology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA.
Papers in Europe PMC - 10Nelson MA2 papers · 2020
Department of Pathology, University of Arizona College of Medicine and College of Pharmacy, Tucson, AZ, USA. Electronic address: mnelson@pathology.arizona.edu.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
—
interventional trials for this specific condition
We could not load trial data for this condition right now.
Data as of 27 July 2026
high confidence
Recruiting interventional trials
From the matched ClinicalTrials.gov set
Trial data could not be loaded for this build. This is not the same as finding zero interventional trials.
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.
"X-linked intellectual disability-global development delay-facial dysmorphism-sacral caudal remnant syndrome" OR "MRXS33" OR "TAF1 X-linked syndromic intellectual disability" OR "X-linked syndromic intellectual disability caused by mutation in TAF1" OR "intellectual developmental disorder, X-linked syndromic 33, X-linked recessive" OR "intellectual disability, X-linked, syndromic type 33" OR "mental retardation, X-linked, syndromic 33" OR "mental retardation, X-linked, syndromic type 33"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
(empty)
Recall-expansion terms: TAF1
Query health: suspect — strategies attempted: phrase, recall-expansion; with hits: phrase
Source errors: trials: Error: HTTP 400 for https://clinicaltrials.gov/api/v2/studies?query.cond=%22X-linked%20intellectual%20disability-global%20development%20delay-facial%20dysmorphism-sacral%20caudal%20remnant%20syndrome%22%20OR%20%22MRXS33%22%20OR%20%22TAF1%20X-linked%20syndromic%20intellectual%20disability%22%20OR%20%22X-linked%20syndromic%20intellectual%20disability%20caused%20by%20mutation%20in%20TAF1%22%20OR%20%22intellectual%20developmental%20disorder%2C%20X-linked%20syndromic%2033%2C%20X-linked%20recessive%22%20OR%20%22intellectual%20disability%2C%20X-linked%2C%20syndromic%20type%2033%22%20OR%20%22mental%20retardation%2C%20X-linked%2C%20syndromic%2033%22%20OR%20%22mental%20retardation%2C%20X-linked%2C%20syndromic%20type%2033%22%20OR%20%22TAF1%22&format=json&pageSize=100&countTotal=true
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 2026-07-27T17:15:42.190Z