ORPHA:178345
Aromatase excess syndrome
Also known as: AEXS · Familial hyperestrogenism · Hereditary prepubertal gynecomastia
Publications
110
56.2th percentile
Trials
1
Interventional, condition-specific
Researchers
519
Distinct authors in sample
Gene link
CYP19A1
Moderate
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
A rare, genetic endocrine disease characterized by increased levels of estrogen due to elevated extraglandular aromatase activity. Males present with heterosexual precocious puberty which manifests with pre- or peripubertal onset of gynecomastia, premature growth spurt, accelerated bone maturation resulting in decreased adult stature, and may present mild hypogonadotropic hypogonadism. Female patients may have isosexual precocious puberty or not have any manifestations at all.
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:0007690
- MeSH:C000591739
- OMIM:139300
- UMLS:C1970109
Additional Mondo synonyms (5)
aromatase excess syndrome · familial hyperestrogenism · gynecomastia, familial, due to increased aromatase activity · gynecomastia, hereditary · hereditary prepubertal gynecomastia
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
Moderate — CYP19A1
- LiteraturePresent
110 matched papers (58 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
1 matched on ClinicalTrials.gov
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?
Probably — there is moderate evidence for CYP19A1.
GenCC classification: Moderate.
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?
110
110 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.
110 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).
58 in the last 10 years · medium confidence · 56.2th percentile (publications denominator)
Phrase hits: 110 · MeSH hits: 0
Who's working on it?
519
Distinct author names in 110 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.
- 01Fukami M14 papers · 2026
Department of Molecular Endocrinology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo, 157-8535, Japan, fukami-m@ncchd.go.jp.
Papers in Europe PMC - 02Ogata T11 papers · 2022
Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
Papers in Europe PMC - 03Shozu M9 papers · 2014
Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
Papers in Europe PMC - 04Binder G4 papers · 2021
Pediatric Endocrinology Section, University-Children's Hospital, Hoppe-Seyler-Str.1, 72076 Tuebingen, Germany. gdbinder@med.uni-tuebingen.de
Papers in Europe PMC - 05Nagasaki K4 papers · 2021
Division of Pediatrics, Niigata University Graduate School of Medicine and Dental Science, Niigata, Japan.
Papers in Europe PMC - 06Bulun SE3 papers · 2013
Division of Reproductive Biology Research, Department of Obstetric and Gynecology, Northwestern University, Chicago, IL 60611, USA. s-bulun@northwestern.edu
Papers in Europe PMC - 07Li X3 papers · 2022
Department of General Surgery, The 301th Hospital of PLA, Beijing, China.
Papers in Europe PMC - 08Martin RM3 papers · 2008
Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Divisão de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, 01065-970 São Paulo, Brasil. reginamm@usp.br
Papers in Europe PMC - 09Miyado M3 papers · 2017
Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
Papers in Europe PMC - 10Nakabayashi K3 papers · 2014Papers in Europe PMC
Clinical research
Is a treatment being tested?
1
interventional trials for this specific condition
1 interventional trial matched this specific condition name; none in our sample are currently recruiting.
Data as of 27 July 2026
1 interventional trial — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 76.8th percentile).
medium confidence · 76.8th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
1 interventional trials matched after quoted-phrase search and title/condition post-filter.
No currently recruiting studies in the matched set. Open the same search on ClinicalTrials.gov.
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.
"Aromatase excess syndrome" OR "Familial hyperestrogenism" OR "Hereditary prepubertal gynecomastia" OR "gynecomastia, familial, due to increased aromatase activity" OR "gynecomastia, hereditary"
MeSH descriptor terms unioned into the query: familial gynecomastia, due to increased aromatase activity
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Aromatase excess syndrome" OR "Familial hyperestrogenism" OR "Hereditary prepubertal gynecomastia" OR "gynecomastia, familial, due to increased aromatase activity" OR "gynecomastia, hereditary" OR "familial gynecomastia, due to increased aromatase activity" OR "CYP19A1"
Recall-expansion terms: CYP19A1
Interventional trials matched via: recall-expansion (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 1 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase, mesh, recall-expansion; with hits: phrase, recall-expansion
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: AEXS
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 2026-07-27T08:49:21.413Z