ORPHA:157801
Mesoaxial synostotic syndactyly with phalangeal reduction
Also known as: MSSD · Syndactyly type 9 · Syndactyly, Malik-Percin type
Query health: suspect — Only one of 3 strategies returned hits (phrase).
Publications
24
36.4th percentile
Trials
0
Interventional, condition-specific
Researchers
161
Distinct authors in sample
Gene link
BHLHA9
Definitive
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
A rare non-syndromic syndactyly characterized by mesoaxial reduction of fingers, complete syndactyly of the 3rd and 4th fingers with synostoses of the corresponding metacarpals and associated single phalanges, malformed thumbs, and hypoplasia and clinodactyly of the 5th finger. Preaxial webbing of toes with terminal phalangeal hypoplasia of all toes has been reported in association.
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:0012271
- MeSH:C563721
- OMIM:609432
- UMLS:C1836206
Additional Mondo synonyms (2)
syndactyly type 9 · syndactyly, Malik-Percin type
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 specific-condition interventional trial, but broader-category trials exist — discuss eligibility with a clinician.
- Gene identifiedPresent
Definitive — BHLHA9
- LiteraturePresent
24 matched papers (19 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; 5 for broader category syndactyly
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 (BHLHA9).
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?
24
24 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.
24 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).
19 in the last 10 years · medium confidence · 36.4th percentile (publications denominator)
Phrase hits: 24 · MeSH hits: 0
Who's working on it?
161
Distinct author names in 24 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.
- 01Ahmad W3 papers · 2019
Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
Papers in Europe PMC - 02Malik S3 papers · 2018
Zentrum für Humangenetik, Philipps-Universität Marburg, Bahnhofstr. 7, Marburg, Germany. malik@staff.uni-marburg.de
Papers in Europe PMC - 03Akarsu NA2 papers · 2014
Department of Medical Genetics, Gene Mapping Laboratory, Hacettepe University Medical Faculty, Sihhiye, 06100 Ankara, Turkey.
Papers in Europe PMC - 04Bertola DR2 papers · 2023
Unidade de Genética, Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil.
Papers in Europe PMC - 05Cormier-Daire V2 papers · 2023
Paris Cité University, Reference Center for Skeletal Dysplasia, INSERM UMR 1163, Imagine Institute, Necker Enfants Malades Hospital (AP-HP), Paris, France.
Papers in Europe PMC - 06Dissanayake VHW2 papers · 2022
Human Genetics Unit, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo, 00800, Sri Lanka.
Papers in Europe PMC - 07Grzeschik KH2 papers · 2014
Zentrum fuer Humangenetik, Philipps-Universitaet Marburg, 35033 Marburg, Germany. Electronic address: grzeschi@staff.uni-marburg.de.
Papers in Europe PMC - 08Hall C2 papers · 2023
Emerita Consultant Paediatric Radiologist at Great Ormond Street Childrens' Hospital, London, UK.
Papers in Europe PMC - 09Koch MC2 papers · 2014
Zentrum fuer Humangenetik, Philipps-Universitaet Marburg, 35033 Marburg, Germany.
Papers in Europe PMC - 10Krakow D2 papers · 2023
Departments of Obstetrics and Gynecology, Orthopaedic Surgery and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, 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 on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present). 5 trials are registered for syndactyly, 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.
medium 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.
5 interventional trials matched syndactyly, the broader category — listed below. Those studies are not counted in the condition-specific total.
Broader category: syndactyly
5
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.
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.
"Mesoaxial synostotic syndactyly with phalangeal reduction" OR "Syndactyly type 9" OR "Syndactyly, Malik-Percin type"
MeSH descriptor terms unioned into the query: Syndactyly, Mesoaxial Synostotic, with Phalangeal Reduction
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Mesoaxial synostotic syndactyly with phalangeal reduction" OR "Syndactyly type 9" OR "Syndactyly, Malik-Percin type" OR "Syndactyly, Mesoaxial Synostotic, with Phalangeal Reduction" OR "BHLHA9" OR "non-syndromic syndactyly" OR "polydactyly-syndactyly-triphalangism"
Recall-expansion terms: BHLHA9, non-syndromic syndactyly, polydactyly-syndactyly-triphalangism
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Parent-category trials query:
"syndactyly"
Query health: suspect — strategies attempted: phrase, mesh, recall-expansion; with hits: phrase
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: MSSD
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 2026-07-27T07:59:44.255Z