RGD uses the Human Disease Ontology (DO, https://disease-ontology.org/) for disease curation across species. RGD automatically downloads each new release of the ontology on a monthly basis. Some additional terms which are required for RGD's curation purposes but are not currently covered in the official version of DO have been added. As corresponding terms are added to DO, these custom terms are retired and the DO terms substituted in existing annotations and subsequently used for curation.
Cortical malformations characterized by grey matter-lined cleft or cyst that extends from the EPENDYMA often to the PIA MATER outer surface. The grey matter that lines the cleft is often POLYMICROGYRIA. It is associated with developmental delay, motor disturbance and seizures. Some patients with schizencephaly have mutations in the EMX2, SIX3, or SHH genes.