Hoyeraal-Hreidarsson syndrome
Findings
No curated finding names Hoyeraal-Hreidarsson syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Hoyeraal-Hreidarsson syndrome (HHS) is a very rare X-linked recessive disorder considered to be a severe variant of dyskeratosis congenita characterized by intrauterine growth retardation, microcephaly, cerebellar hypoplasia, progressive combined immune deficiency and aplastic anemia.
Definition from the Mondo Disease Ontology (MONDO:0018045), read 2026-09-29. CC BY 4.0.
Features
28 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Cerebellar hypoplasiaHPOHP:0001321
- Very frequent (80% to 99% of cases)
- Dermal atrophyHPOHP:0004334
- Very frequent (80% to 99% of cases)
- Failure to thriveHPOHP:0001508
- Very frequent (80% to 99% of cases)
- Global developmental delayHPOHP:0001263
- Very frequent (80% to 99% of cases)
- ImmunodeficiencyHPOHP:0002721
- Very frequent (80% to 99% of cases)
- Intellectual disabilityHPOHP:0001249
- Very frequent (80% to 99% of cases)
- Intrauterine growth retardationHPOHP:0001511
- Very frequent (80% to 99% of cases)
- MicrocephalyHPOHP:0000252
- Very frequent (80% to 99% of cases)
- Short statureHPOHP:0004322
- Very frequent (80% to 99% of cases)
- ThrombocytopeniaHPOHP:0001873
- Very frequent (80% to 99% of cases)
- Abnormality of coagulationHPOHP:0001928
- Frequent (30% to 79% of cases)
- AnemiaHPOHP:0001903
- Frequent (30% to 79% of cases)
Show the remaining 16
- Cerebral cortical atrophyHPOHP:0002120
- Frequent (30% to 79% of cases)
- Excessive wrinkled skinHPOHP:0007392
- Frequent (30% to 79% of cases)
- Generalized hyperpigmentationHPOHP:0007440
- Frequent (30% to 79% of cases)
- Generalized hypopigmentation of hairHPOHP:0011358
- Frequent (30% to 79% of cases)
- HypertoniaHPOHP:0001276
- Frequent (30% to 79% of cases)
- Nail dystrophyHPOHP:0008404
- Frequent (30% to 79% of cases)
Genes
6 genes
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- ACDHGNC:25070
- Supportive · Orphanet · Autosomal dominant · 2021
- DKC1HGNC:2890
- Supportive · Orphanet · Autosomal dominant · 2021
- PARNHGNC:8609
- Supportive · Orphanet · Autosomal dominant · 2021
- RTEL1HGNC:15888
- Supportive · Orphanet · Autosomal dominant · 2021
- TERTHGNC:11730
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
1 name
Resolves to: Hoyeraal-Hreidarsson syndrome
- Also called
- progressive pancytopenia-immunodeficiency-cerebellar hypoplasia syndrome