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.
A disease characterized by developmental delay and impaired intellectual development with a high prevalence of motor disease, dysmorphisms, and psychiatric conditions, including autism spectrum disorder, caused by heterozygous mutation in the MSL2 gene on chromosome 3q22.