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.
Term:
neurodevelopmental disorder with seizures and gingival overgrowth
A syndrome characterized by a variable phenotype primarily including seizures, gingival overgrowth, a prominent mandible or cherubism, and mental deterioration that has_material_basis_in homozygous or compound heterozygous mutation in the TBC1D2B gene on chromosome 15q24. Other more variable features include coarse facial features, optic atrophy, sensorineural hearing loss, ataxia, hypotonia, delayed development or developmental regression, cerebellar or cerebral atrophy, and enlarged brain ventricles. (DO)