Mondo is GA4GH’s first formally endorsed externally-developed standard, coordinated by the Monarch Initiative driver project. The working session maps how Mondo interoperates across the GA4GH ecosystem and grows the community that sustains it. Mondo bridges OMIM’s Mendelian knowledge toward clinical classifications (ICD-11) on one side, and serves as the disease-concept resource, which can further be referenced by the disease-concept resource that the Variant Representation and Variant Annotation Specifications (VRS/VA-Spec), the Data Use Ontology (DUO), Beacon v2 discovery, Phenopackets, and in partnership with HL7 and OHDSI to support FHIR and OMOP terminology services. Using a coverage-cascade method, we will present a preliminary interoperability map across these standards: where Mondo is already adopted (working), where Mondo has formalised the knowledge but the standard has not yet bound to it (ready), and where the concept exists only in other upstream sources and Driver Projects, such as OMIM or EGA (gap).

We will (1) walk through the map and a live, clinician-facing demo linking variants, annotations, disease concepts, and queries; (2) invite each GA4GH standard's maintainers to correct any findings and propose enhancements; and (3) onboard new Mondo contributors, and host a call for “bring your own standard or use case.”

The session produces a community-validated interoperability landscape and a short recommendations document, intended as the basis for a publication, led by the Monarch Initiative.