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ORPHA:3322

Hoyeraal-Hreidarsson syndrome

low confidenceDisorder

Also known as: Progressive pancytopenia-immunodeficiency-cerebellar hypoplasia syndrome

Publications

561

Trials

3

Interventional, condition-specific

Researchers

1,141

Distinct authors in sample

Gene link

—

Readiness

3/6

Stages with a signal

Clinical definition (Orphanet)

A rare X-linked syndromic considered to be a severe variant of dyskeratosis congenita characterized by intrauterine growth retardation, microcephaly, cerebellar hypoplasia, combined immune deficiency and aplastic anemia.

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.

Orphanet entry

Cross-references

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

Additional Mondo synonyms (1)

progressive pancytopenia-immunodeficiency-cerebellar hypoplasia 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.

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    561 matched papers (362 in last 10 years) Source

  3. Phenotype characterisedPresent

    28 HPO annotations (e.g. Ataxia; Sparse scalp hair; Premature graying of hair) 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

    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?

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

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

Phenotypes (Monarch / HPO)

28

Associated phenotypes · MONDO:0018045

  • Ataxia
  • Sparse scalp hair
  • Premature graying of hair
  • Cerebral calcification
  • Neoplasm

Showing 5 of 28 — 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?

561

561 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.

561 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).

362 in the last 10 years · low confidence

Phrase hits: 561 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,141

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
    Savage SA23 papers · 2026

    Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.

    Papers in Europe PMC
  2. 02
    Giri N10 papers · 2025

    Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.

    Papers in Europe PMC
  3. 03
    Niewisch MR10 papers · 2025

    Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD.

    Papers in Europe PMC
  4. 04
    McReynolds LJ9 papers · 2025

    Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD.

    Papers in Europe PMC
  5. 05
    Revy P9 papers · 2025

    INSERM UMR 1163, Laboratory of Genome Dynamics in the Immune System, Équipe Labellisée LIGUE 2023, Paris, France.

    Papers in Europe PMC
  6. 06
    Alter BP7 papers · 2024

    Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.

    Papers in Europe PMC
  7. 07
    Callebaut I7 papers · 2025

    Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris 75005, France.

    Papers in Europe PMC
  8. 08
    Tzfati Y7 papers · 2026

    Department of Genetics, The Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel.

    Papers in Europe PMC
  9. 09
    Kaestner KH5 papers · 2026

    Department of Genetics and Digestive and Liver Center, University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: kaestner@pennmedicine.upenn.edu.

    Papers in Europe PMC
  10. 10
    Kannengiesser C5 papers · 2026

    U1152 INSERM, Department of Genetics, Assistance Publique-Hôpitaux de Paris, Bichat Hospital, Paris Cité University, F-75018 Paris, France.

    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 11 September 2026

3 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 86.7th percentile).

low confidence · 86.7th 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.

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 2026-07-29

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).

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 Hoyeraal-Hreidarsson 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.

"Hoyeraal-Hreidarsson syndrome" OR "Progressive pancytopenia-immunodeficiency-cerebellar hypoplasia syndrome"

Run this search on Europe PMC

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

"Hoyeraal-Hreidarsson syndrome" OR "Progressive pancytopenia-immunodeficiency-cerebellar hypoplasia syndrome"

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: 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
  • No label/synonym collisions with other diseases in this corpus
  • Publication count (561) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-26T22:52:20.583Z