holoprosencephaly 2
Findings
No curated finding names holoprosencephaly 2 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A rare disorder characterized by the partial separation of the cerebral hemispheres. It is associated with mutations in the SIX3 gene.
Definition from the Mondo Disease Ontology (MONDO:0007999), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
- Onset and course
- Congenital onset
HPO, annotations 2026-09-02
Features
17 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.
- Global developmental delayHPOHP:0001263
- 1 of 1 reported patient
- HypotelorismHPOHP:0000601
- 4 of 4 reported patients
- Bilateral cleft lipHPOHP:0100336
- 3 of 4 reported patients
- Bilateral cleft palateHPOHP:0100337
- 3 of 4 reported patients
- Alobar holoprosencephalyHPOHP:0006988
- 2 of 4 reported patients
- MicrocephalyHPOHP:0000252
- 2 of 4 reported patients
- ProptosisHPOHP:0000520
Show the remaining 5
- MicrophthalmiaHPOHP:0000568
- 1 of 4 reported patients
- Midface retrusionHPOHP:0011800
- 1 of 4 reported patients
- Remnants of the hyaloid vascular systemHPOHP:0007968
- 1 of 4 reported patients
- Semilobar holoprosencephalyHPOHP:0002507
- 1 of 4 reported patients
- HoloprosencephalyHPOHP:0001360
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.
- SIX3HGNC:10889
- Definitive · G2P · Autosomal dominant · 2015
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2021
- Strong · Laboratory for Molecular Medicine · Autosomal dominant · 2020
- Strong · PanelApp Australia · Autosomal dominant · 2025
Where it sits
- A kind of
Other names
4 names
Resolves to: holoprosencephaly 2
- Also called
- holoprosencephaly caused by mutation in SIX3holoprosencephaly type 2HPE2SIX3 holoprosencephaly