bilateral generalized polymicrogyria
Findings
No curated finding names bilateral generalized polymicrogyria yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Bilateral generalized polymicrogyria is a rare neurological disorder that affects the cerebral cortex (the outer surface of the brain). This is the most widespread form of polymicrogyria and typically affects the entire surface of the brain. Signs and symptoms include severe intellectual disability, problems with movement, and seizures that are difficult or impossible to treat. While the exact cause of bilateral generalized polymicrogyria is not fully understood, it is thought to be due to improper brain development during embryonic growth. Most cases appear to follow an autosomal recessive pattern of inheritance. Treatment is based on the signs and symptoms present in each person.
Definition from the Mondo Disease Ontology (MONDO:0013907), read 2026-09-29. CC BY 4.0.
Features
51 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.
- Delayed ability to walkHPOHP:0031936
- Very frequent (80% to 99% of cases)
- Delayed gross motor developmentHPOHP:0002194
- Very frequent (80% to 99% of cases)
- Profound global developmental delayHPOHP:0012736
- Very frequent (80% to 99% of cases)
- Abnormality of movementHPOHP:0100022
- Frequent (30% to 79% of cases)
- Atypical behaviorHPOHP:0000708
- Frequent (30% to 79% of cases)
- Axial hypotoniaHPOHP:0008936
- Frequent (30% to 79% of cases)
Show the remaining 39
- Spastic tetraplegiaHPOHP:0002510
- Frequent (30% to 79% of cases)
- SpasticityHPOHP:0001257
- Frequent (30% to 79% of cases)
- Abnormal hippocampus morphologyHPOHP:0025100
- Occasional (5% to 29% of cases)
- Atonic seizureHPOHP:0010819
- Occasional (5% to 29% of cases)
- Autistic behaviorHPOHP:0000729
- Occasional (5% to 29% of cases)
- Bilateral tonic-clonic seizureHPOHP:0002069
- 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.
- RTTNHGNC:18654
- Moderate · Ambry Genetics · Autosomal recessive · 2018
Where it sits
Other names
1 name
Resolves to: bilateral generalized polymicrogyria
- Also called
- microcephaly, short stature, and polymicrogyria with seizures