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.
This is a neurodevelopmental disorder characterized by infantile hypotonia, global developmental delay, mild motor and speech delay, and mild to moderately impaired intellectual development. Patients have prominent dysmorphic facial features, including hypertelorism, downslanting palpebral fissures, strabismus, and small low-set ears.