polymicrogyria with optic nerve hypoplasia
Findings
No curated finding names polymicrogyria with optic nerve hypoplasia yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A rare genetic syndrome with central nervous system malformations characterized by severe developmental delay, neonatal hypotonia, seizures, optic nerve hypoplasia and distinct central nervous system malformations including extensive bilateral polymicrogyria, dysplastic or absent corpus callosum and malformed brainstem with loss of demarcation of the pontomedullary junction.
Definition from the Mondo Disease Ontology (MONDO:0013172), read 2026-09-29. CC BY 4.0.
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.
- Abnormality of the nervous systemHPOHP:0000707
- Very frequent (80% to 99% of cases)
- Absent speechHPOHP:0001344
- Very frequent (80% to 99% of cases)
- ColpocephalyHPOHP:0030048
- Very frequent (80% to 99% of cases)
- HyporeflexiaHPOHP:0001265
- Very frequent (80% to 99% of cases)
- Neonatal hypotoniaHPOHP:0001319
- Very frequent (80% to 99% of cases)
- Optic nerve hypoplasiaHPOHP:0000609
- Very frequent (80% to 99% of cases)
Show the remaining 2
- Hypoplasia of the brainstemHPOHP:0002365
- Occasional (5% to 29% of cases)
- Infantile spasmsHPOHP:0012469
- Occasional (5% to 29% of cases)
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.
- TUBA8HGNC:12410
- Supportive · Orphanet · Autosomal recessive · 2021
- Limited · Labcorp Genetics (formerly Invitae) · Unknown · 2018
- Limited · G2P · Autosomal recessive · 2023
- Disputed Evidence · ClinGen · Autosomal recessive · 2023
- Disputed Evidence · PanelApp Australia · Autosomal recessive · 2025