The Swiss Personalized Health Network (SPHN) is a Swiss research infrastructure initiative that aims to facilitate the exchange of health-related data in a FAIR manner. The SPHN Dataset and SPHN RDF Schema form an essential part of the SPHN Semantic Interoperability Framework, which currently covers mostly clinical routine data. To facilitate the integration of omics data produced by the SPHN National Data Streams, a genomics extension was developed. This was done in close collaboration with clinicians, researchers, bioinformaticians, and data managers, from Swiss university hospitals, academic research groups and the omics platforms. Here, we present the genomics extension of the SPHN RDF Schema, which can be used to semantically describe genomics experiments and covers both clinical and research domains. The schema centers around the general omics process flow, with concepts that denote the individual steps, such as sample processing, assay, and data processing. Genomics-specific specializations are provided, such as library preparation, sequencing assay, and sequencing analysis. The schema also facilitates in capturing other important omics metadata, such as information about the sequencing instrument, standard operating procedure, and quality control metrics. The extension aligns with existing semantic data models and reuses common biomedical vocabularies, such as EDAM, OBI and FAIR genomes, as value sets, thereby facilitating semantic interoperability. It will be used to FAIRify data that is produced within the Swiss network and to facilitate sharing this data as one knowledge graph for reuse among its participants.