ACTB-associated syndromic thrombocytopenia
Findings
No curated finding names ACTB-associated syndromic thrombocytopenia yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A syndromic constitutional thrombocytopenia caused by a variation in the ACTB gene, associated with developmental delay, mild intellectual disability, microcephaly, and thrombocytopenia with platelet anisotropy and enlarged platelets. Unlike many inherited platelet disorders, spontaneous bleeding is often limited, and the phenotype reflects a combined disturbance of platelet formation and neurodevelopmental and craniofacial patterning.
Definition from the Mondo Disease Ontology (MONDO:0100433), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
- Onset and course
- Congenital onset · Infantile onset
HPO, annotations 2026-09-02
Features
35 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.
- Gray matter heterotopiaHPOHP:0002282
- 1 of 1 reported patient
- Increased mean platelet volumeHPOHP:0011877
- 5 of 5 reported patients
- Platelet anisocytosisHPOHP:0032438
- 4 of 4 reported patients
- PolyhydramniosHPOHP:0001561
- 1 of 1 reported patient
- Prominent metopic ridgeHPOHP:0005487
- 1 of 1 reported patient
- ThrombocytopeniaHPOHP:0001873
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.
- ACTBHGNC:132
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Moderate · Ambry Genetics · Autosomal dominant · 2024
- Moderate · ClinGen · Autosomal dominant · 2024
Where it sits
Other names
3 names
Resolves to: ACTB-associated syndromic thrombocytopenia
- Also called
- ACTB-ASTACTB-related syndromic thrombocytopeniathrombocytopenia 8, with dysmorphic features and developmental delay