Core Summary/Abstract Studies of Superfund toxicants require novel mouse models, careful, high-throughput analyses of hormones, cytokines and small molecule metabolites, and informatics analyses of large datasets to pioneer new findings in the detection of environmental toxicants and health effects of exposure. The UC San Diego Superfund Research Center Genetics and Metabolomics Core facility will provide state-of-the-art molecular biology services for generation of murine models of toxicant exposure as well as cutting-edge analytical services for sensitive, high-throughput assay of hormones and small molecule metabolites and their informatic analyses. This Core will interface with all six proposed research projects. Comprehensive approaches for modifying the mouse genome are provided including DNA microinjection, embryonic stem cell homologous recombination, CRISPR/Cas9 mutagenesis, and blastocyst injection, specifically tailored to UCSD Superfund projects. Furthermore, metabolomics services will be provided, allowing for measure of hormones, growth factors, and thousands of small molecule metabolites (both targeted and untargeted) using a Luminex magnetic bead analyzer and liquid chromatography-mass spectrometry based approaches. Samples for analysis will include human and mouse biospecimens (plasma, urine, and stool) as well as community plant, water, and soil samples. Bioinformatics services will provide in-depth analyses of large datasets resulting from transcriptomics, cistromics, and metabolomics. This core provides centralized, cost-effective, efficient, technically sophisticated services that are crucial to the success of all six projects in the UC San Diego Superfund Research Center.