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ORPHA:8

47,XYY syndrome

medium confidenceDisorder

Also known as: Double Y syndrome · Jacobs syndrome · XYY syndrome · Y disomy

Publications

2,975

88.8th percentile

Trials

1

Interventional, condition-specific

Researchers

1,228

Distinct authors in sample

Gene link

—

Readiness

3/6

Stages with a signal

Clinical definition (Orphanet)

A rare sex chromosome aneuploidy where males receive an additional Y chromosome, that is characterized clinically by tall stature evident from childhood, macrocephaly, facial features (mild hypertelorism, low set ears, a mildly flat malar region), speech delay and an increased risk for social and emotional difficulties, attention deficit hyperactive disorder and autistic spectrum disorder.

How rare: 1-5 / 10 000 — about one to five people per ten thousand (still uncommon, but less ultra-rare).

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (5)

47,XYY · Double Y · XYY Syndrome · XYY karyotype · disomy Y

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.

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    2,975 matched papers (1,302 in last 10 years) Source

  3. Phenotype characterisedPresent

    45 HPO annotations (e.g. Tics; Pes planus; Asthma) Source

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. 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?

Not yet — the cause hasn't been pinned down in GenCC.

No strong gene–disease assertion joined for this Orphanet entity.

Phenotypes (Monarch / HPO)

45

Associated phenotypes · MONDO:0019339

  • Tics
  • Pes planus
  • Asthma
  • Azoospermia
  • Oligozoospermia

Showing 5 of 45 — 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?

2,975

2,975 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

2,975 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).

1,302 in the last 10 years · medium confidence · 88.8th percentile (publications denominator)

Phrase hits: 2,975 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,228

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.

  1. 01
    Raznahan A16 papers · 2026

    National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.

    Papers in Europe PMC
  2. 02
    Ross J13 papers · 2026

    Department of Pediatrics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.

    Papers in Europe PMC
  3. 03
    Rau S10 papers · 2026

    Center for Autism Spectrum Disorders and Division of Neuropsychology, Children's National Hospital, Washington, DC, USA.

    Papers in Europe PMC
  4. 04
    Tartaglia N10 papers · 2026

    Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA.

    Papers in Europe PMC
  5. 05
    Liu S9 papers · 2026

    Section On Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health Intramural Research Program, Bethesda, MD, 20892, USA.

    Papers in Europe PMC
  6. 06
    Schaffer L9 papers · 2026

    Section On Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health Intramural Research Program, Magnuson Clinical Center, Room 4N242, MSC 1367, Bethesda, MD, 20814, USA.

    Papers in Europe PMC
  7. 07
    Bothwell S8 papers · 2026

    Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado.

    Papers in Europe PMC
  8. 08
    Gravholt CH8 papers · 2023

    Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.

    Papers in Europe PMC
  9. 09
    Davis S7 papers · 2026

    Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado.

    Papers in Europe PMC
  10. 10
    Davis SM7 papers · 2025

    eXtraordinarY Kids Clinic and Research Program, Children's Hospital Colorado, Aurora, Colorado, USA.

    Papers 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 11 September 2026

1 interventional trial — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 80.1th percentile).

medium confidence · 80.1th 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.

Observational and natural-history studies

2 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.

Recruiting or not-yet-recruiting

Open the complete matched search on ClinicalTrials.gov

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 92 · after dedupe 91 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 91 · dropped 0 · fetched 2026-07-29

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).

Uncertain / not reviewed (91)

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 47,XYY syndrome — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This 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.

("47,XYY syndrome" OR "Double Y syndrome" OR "Jacobs syndrome" OR "XYY syndrome" OR "Y disomy" OR "47,XYY" OR "Double Y" OR "XYY karyotype" OR "disomy Y")

Run this search on Europe PMC

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"47,XYY syndrome" OR "Double Y syndrome" OR "Jacobs syndrome" OR "XYY syndrome" OR "Y disomy" OR "47,XYY" OR "Double Y" OR "XYY karyotype" OR "disomy Y"

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: 1 interventional · 2 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: ok — strategies attempted: phrase; with hits: phrase

Run this search on ClinicalTrials.gov

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • No synonyms dropped by stoplist
  • "Jacobs syndrome" also appears on ORPHA:2848

Ingested 2026-07-26T12:04:05.303Z