multisystemic smooth muscle dysfunction syndrome
Findings
No curated finding names multisystemic smooth muscle dysfunction syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A spectrum of conditions caused by monoallelic pathogenic variants in ACTA2. Phenotypes can present in isolation or in combination and can include, but are not limited to: cardiovascular manifestations (heritable thoracic aortic aneurysm and dissection, coronary artery disease, patent ductus arteriosus, aortic pulmonary window, and/or early-onset atherosclerosis), smooth muscle cell dysfunction (hypoperistalsis, hydronephrosis and hydroureter, megacystis), ophthalmological manifestations (retinal vessel disease, congenital mydriasis and iris flocculi/hypoplasia), and a Moyamoya-like cerebrovascular disease.
Definition from the Mondo Disease Ontology (MONDO:0013452), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
- Onset and course
- Congenital onset
HPO, annotations 2026-09-02
Features
15 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.
- MydriasisHPOHP:0011499
- 5 of 5 reported patients · Congenital onset
- Patent ductus arteriosusHPOHP:0001643
- 5 of 5 reported patients
- Thoracic aortic aneurysmHPOHP:0012727
- 5 of 5 reported patients
- DysgyriaHPOHP:0032398
- 12 of 13 reported patients
- TachypneaHPOHP:0002789
- 4 of 5 reported patients · Neonatal onset
- Pulmonary artery dilatationHPO
Genes
2 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.
- ACTA2HGNC:130
- Definitive · ClinGen · Autosomal dominant · 2025
- Definitive · G2P · Autosomal dominant · 2018
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2023
- Supportive · Orphanet · Unknown · 2021
- HGNC:31532HGNC:31532
- Limited · PanelApp Australia · Autosomal dominant · 2025
Where it sits
- Narrower terms (2)
Other names
1 name
Resolves to: multisystemic smooth muscle dysfunction syndrome
- Also called
- ACTA2-related smooth muscle dysfunction syndrome