juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome
Findings
No curated finding names juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
An autosomal dominant syndrome caused by pathogenic variants in the SMAD4 gene, characterized by the combined features of juvenile polyposis syndrome (JPS) and hereditary hemorrhagic telangiectasia (HHT). JPS features include multiple juvenile polyps in the gastrointestinal tract and an increased risk of gastrointestinal cancers. HHT features include arteriovenous malformations (AVMs) and telangiectasias.
Definition from the Mondo Disease Ontology (MONDO:0008278), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
- Onset and course
- Middle age onset · Juvenile onset · Childhood onset
HPO, annotations 2026-09-02
Features
14 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.
- Cavernous hemangiomaHPOHP:0001048
- 1 of 1 reported patient
- Cerebral hemorrhageHPOHP:0001342
- 2 of 2 reported patients
- Cyanotic episodeHPOHP:0200048
- 1 of 1 reported patient
- Juvenile colonic polyposisHPOHP:0012198
- 12 of 12 reported patients
- Juvenile gastrointestinal polyposisHPOHP:0004784
- 2 of 2 reported patients
- PancytopeniaHPOHP:0001876
Genes
1 gene
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.
- SMAD4HGNC:6770
- Definitive · ClinGen · Autosomal dominant · 2023
- Definitive · G2P · Autosomal dominant · 2024
- Strong · Genomics England PanelApp · Autosomal dominant · 2021
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2021
- Strong · PanelApp Australia · Autosomal dominant · 2025
Where it sits
Other names
1 name
Resolves to: juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome
- Also called
- SMAD4-related juvenile polyposis/hemorrhagic telangiectasia syndrome