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.
Oocyte maturation defect-6 (OOMD6) is characterized by primary infertility due to defective sperm-binding to an abnormally thin zona pellucida in patient oocytes. Successful pregnancy may be achieved by intracytoplasmic sperm injection in these patients. OOMD6 is caused by homozygous mutation in the ZP2 gene on chromosome 16p12. (OMIM)