ORPHA:647
Nijmegen breakage syndrome
Also known as: AT V1 · Ataxia-telangiectasia, variant 1 · Berlin breakage syndrome · Immunodeficiency-microcephaly-chromosomal instability syndrome · Microcephaly-immunodeficiency-lymphoid malignancy syndrome · NBS · Seemanova syndrome type 2
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
815,396
Trials
3
Interventional, condition-specific
Researchers
1,253
Distinct authors in sample
Gene link
NBN
Definitive
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
A rare, genetic chromosomal instability syndrome presenting at birth with microcephaly, facial features which become more noticeable with age, growth delay, recurring sinopulmonary infections and extremely high frequency of malignancies.
How rare: How common this is has not been clearly measured.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0009623
- MeSH:D049932
- OMIM:251260
- UMLS:C0398791
- NCIT:C4692
Additional Mondo synonyms (4)
NBs · Seemanova syndrome · ataxia-telangiectasia, variant 1 · immunodeficiency-microcephaly-chromosomal instability syndrome
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
An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.
- Gene identifiedPresent
Definitive — NBN
- LiteraturePresent
815,396 matched papers (747,269 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 trialPresent
3 matched on ClinicalTrials.gov (2 recruiting in sample)
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 (NBN).
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?
815,396
815,396 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=5449) is 41.
815,396 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).
747,269 in the last 10 years · low confidence
Phrase hits: 815,396 · MeSH hits: 0
Who's working on it?
1,253
Distinct author names in 200 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.
- 01
- 02Wang X5 papers · 2026
School of Psychological and Cognitive Sciences, Peking University, Beijing, China.
Papers in Europe PMC - 03Zhang Y5 papers · 2026
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong, China.
Papers in Europe PMC - 04Chen X4 papers · 2026
Northeastern University, Boston, Massachusetts, United States.
Papers in Europe PMC - 05Liu L4 papers · 2026
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong, China.
Papers in Europe PMC - 06Pastorczak A4 papers · 2025
Department of Pediatrics, Oncology and Hematology, Medical University of Lodz, Lodz, Poland. agata.pastorczak@umed.lodz.pl.
Papers in Europe PMC - 07Zhao L4 papers · 2026
Research Centre Jülich, Institute of Neuroscience and Medicine (INM-1), 52425, Jülich, Germany.
Papers in Europe PMC - 08Bartolomeo P3 papers · 2026
Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié-Salpêtrière, Paris, France. Electronic address: paolo.bartolomeo@icm-institute.org.
Papers in Europe PMC - 09Cattaneo S3 papers · 2026
Unit of Neuroscience, Department of Medicine and Surgery, University of Parma, Parma, Italy.
Papers in Europe PMC - 10Chen Y3 papers · 2026
Center for Perceptual Systems, The University of Texas at Austin, Austin, TX, USA.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
3
interventional trials for this specific condition
3 interventional trials matched this specific condition name; 2 currently recruiting in our sample.
Data as of 27 July 2026
3 interventional trials — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 85.1th percentile).
low confidence · 85.1th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
3 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT06198842·RECRUITING·Low Dose Treosulfan Based Conditioning Regimen and PTCy in HSCT for Nijmegen Breakage Syndrome
Conditions: Nijmegen Breakage Syndrome·Matched via name phrase
- NCT07316595·NOT YET RECRUITING·Study of Treosulfan-Based Conditioning for HSCT in Nijmegen Breakage Syndrome
Conditions: HSCT · Nijmegen Breakage Syndrome · Treosulfan Based Conditioning·Matched via name phrase
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.
"Nijmegen breakage syndrome" OR "AT V1" OR "Ataxia-telangiectasia, variant 1" OR "Berlin breakage syndrome" OR "Immunodeficiency-microcephaly-chromosomal instability syndrome" OR "Microcephaly-immunodeficiency-lymphoid malignancy syndrome" OR "Seemanova syndrome type 2" OR "Seemanova syndrome"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Nijmegen breakage syndrome" OR "AT V1" OR "Ataxia-telangiectasia, variant 1" OR "Berlin breakage syndrome" OR "Immunodeficiency-microcephaly-chromosomal instability syndrome" OR "Microcephaly-immunodeficiency-lymphoid malignancy syndrome" OR "Seemanova syndrome type 2" OR "Seemanova syndrome" OR "NBN"
Recall-expansion terms: NBN
Interventional trials matched via: phrase (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 3 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, recall-expansion; with hits: phrase
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: NBS
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
- Publication count (815396) is extremely high with unknown/missing prevalence — treat as possible over-matching, not proven research intensity
Ingested 2026-07-26T14:43:48.440Z