ORPHA:75374
Bradyopsia
Also known as: PERRS · Prolonged electroretinal response suppression
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
34,892
Trials
0
Interventional, condition-specific
Researchers
644
Distinct authors in sample
Gene link
RGS9, RGS9BP
Strong
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
A rare genetic retinal disorder characterized by childhood-onset of markedly delayed visual adaptation to both dark and light conditions, marked difficulties tracking moving objects, and mild photophobia. Visual acuity is variably reduced, while color vision is unaffected.
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:0012033
- MeSH:C564243
- UMLS:C1842073
Additional Mondo synonyms (2)
bradyopsia · prolonged electroretinal response suppression
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.”
3/6 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
Strong — RGS9, RGS9BP
- LiteraturePresent
34,892 matched papers (16,841 in last 10 years) Source
- Phenotype characterisedPresent
11 HPO annotations (e.g. Photophobia; Visual impairment; Difficulty adjusting to changes in luminance) 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?
Yes — we know a specific gene responsible (RGS9, RGS9BP).
GenCC classification: Strong.
Phenotypes (Monarch / HPO)
11
Associated phenotypes · MONDO:0012033
- Photophobia
- Visual impairment
- Difficulty adjusting to changes in luminance
- Bradyopsia
Showing 4 of 11 — 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?
34,892
34,892 papers — among the better-studied rare conditions, though still a fraction of common-disease literature (breast cancer: over 700,000). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
34,892 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).
16,841 in the last 10 years · low confidence
Phrase hits: 120 · MeSH hits: 0
Who's working on it?
644
Distinct author names in 120 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.
- 01Michaelides M8 papers · 2022
Moorfields Eye Hospital City Road Campus, London, UK michel.michaelides@ucl.ac.uk.
Papers in Europe PMC - 02Benaroudj N6 papers · 2023
Institut Pasteur, Université Paris Cité, Biologie des Spirochètes, CNRS UMR 6047, F-75015 Paris, France.
Papers in Europe PMC - 03Carroll J6 papers · 2026
Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
Papers in Europe PMC - 04Chen CK5 papers · 2019
Departments of Ophthalmology, Neuroscience, and Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030.
Papers in Europe PMC - 05Picardeau M5 papers · 2021
Institut Pasteur, Université de Paris, Biologie des Spirochètes, F-75015 Paris, France.
Papers in Europe PMC - 06Dubis AM4 papers · 2019
UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK. a.dubis@ucl.ac.uk.
Papers in Europe PMC - 07Dubra A4 papers · 2021
Department of Ophthalmology, Stanford University, Palo Alto, CA, Unites States.
Papers in Europe PMC - 08
- 09Martemyanov KA4 papers · 2021
Department of Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA.
Papers in Europe PMC - 10Robson AG4 papers · 2022
Department of Electrophysiology, Moorfields Eye Hospital, 162 City Road, London, UK. anthony.robson@moorfields.nhs.uk.
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.
low 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 2026-07-30
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 Bradyopsia — 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.
("Bradyopsia" OR "PERRS" OR "Prolonged electroretinal response suppression") OR (MESH:"Prolonged Electroretinal Response Suppression") OR ("RGS9" OR "RGS9 syndrome" OR "RGS9-related" OR "RGS9BP" OR "RGS9BP syndrome" OR "RGS9BP-related")MeSH descriptor terms unioned into the query: Prolonged Electroretinal Response Suppression
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Bradyopsia" OR "PERRS" OR "Prolonged electroretinal response suppression"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, mesh; with hits: phrase
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is short or not clearly distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
- Publication count (34892) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity
Ingested 2026-07-27T01:47:25.199Z