ORPHA:137831
X-linked intellectual disability-cerebellar hypoplasia syndrome
Also known as: OPHN1 syndrome · Oligophrenin-1 syndrome
Query health: suspect — Only one of 3 strategies returned hits (phrase).
Publications
25
34.8th percentile
Trials
0
Interventional, condition-specific
Researchers
188
Distinct authors in sample
Gene link
OPHN1
Definitive
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
X-linked intellectual deficit-cerebellar hypoplasia, also known as OPHN1 syndrome, is a rare syndromic form of cerebellar dysgenesis characterized by moderate to severe intellectual deficit and cerebellar abnormalities.
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:0010337
- MeSH:C537456
- OMIM:300486
- UMLS:C1845366
Additional Mondo synonyms (1)
intellectual developmental disorder, X-linked syndromic, Billuart type, X-linked recessive
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 matched interventional trial; the gene is known and literature exists — preclinical or natural-history work may still be the practical next step.
- Gene identifiedPresent
Definitive — OPHN1
- LiteraturePresent
25 matched papers (17 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?
Yes — we know a specific gene responsible (OPHN1).
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?
25
25 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.
25 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).
17 in the last 10 years · high confidence · 34.8th percentile (publications denominator)
Phrase hits: 25 · MeSH hits: 0
Who's working on it?
188
Distinct author names in 25 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.
- 01Anzai H2 papers · 2026
Division of Ophthalmology, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo, 157-8535, Japan.
Papers in Europe PMC - 02Fukami M2 papers · 2026
Department of Molecular Endocrinology, National Research Institute for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo, 157-8535, Japan. fukami-m@ncchd.go.jp.
Papers in Europe PMC - 03Hanazono Y2 papers · 2026
Medical Research Laboratory, Institute of Integrated Research, Institute of Science Tokyo, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
Papers in Europe PMC - 04
- 05Hirayama J2 papers · 2026
Faculty of Education, Bunkyo University, Saitama, Japan.
Papers in Europe PMC - 06Ito N2 papers · 2026
Medical Research Laboratory, Institute of Integrated Research, Institute of Science Tokyo, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
Papers in Europe PMC - 07Kofuji S2 papers · 2026
Medical Research Laboratory, Institute of Integrated Research, Institute of Science Tokyo, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
Papers in Europe PMC - 08Litvan I2 papers · 2023
University of California, San Diego, San Diego, California.
Papers in Europe PMC - 09Matsubara K2 papers · 2026
Integrated Center for Women's Health, National Research Institute for Child Health and Development, Tokyo, Japan.
Papers in Europe PMC - 10Nishina H2 papers · 2026
Medical Research Laboratory, Institute of Integrated Research, Institute of Science Tokyo, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan. nishina.dbio@mri.tmd.ac.jp.
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.
General rare disease registries you may be eligible for
These studies enroll across many rare conditions. They are not counted as evidence that anyone is studying this specific disease.
- NCT01793168·RECRUITING·Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford
Conditions: Rare Disorders · Undiagnosed Disorders · Disorders of Unknown Prevalence · Cornelia De Lange Syndrome
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-cerebellar hypoplasia syndrome" OR "OPHN1 syndrome" OR "Oligophrenin-1 syndrome" OR "intellectual developmental disorder, X-linked syndromic, Billuart type, X-linked recessive"
MeSH descriptor terms unioned into the query: Mental retardation, X-linked, with cerebellar hypoplasia and distinctive facial appearance
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"X-linked intellectual disability-cerebellar hypoplasia syndrome" OR "OPHN1 syndrome" OR "Oligophrenin-1 syndrome" OR "intellectual developmental disorder, X-linked syndromic, Billuart type, X-linked recessive" OR "Mental retardation, X-linked, with cerebellar hypoplasia and distinctive facial appearance" OR "OPHN1"
Recall-expansion terms: OPHN1
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, mesh, 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 2026-07-27T07:29:49.937Z