The Peltz laboratory develops and applies state of the art genetic, genomic and stem cell technologies to its research programs. These methodologies are used to discover the mechanisms mediating disease susceptibility and drug response, and to develop new therapies. As one example, we developed a novel computational genetic analysis method, which has identified genetic factors affecting disease susceptibility and biomedical responses in mouse models. Over 25 genetic factors affecting susceptibility to drug addiction, chronic pain, infectious diseases, and others have already been identified. An ongoing effort is now analyzing 8000 biomedical responses in panels of inbred mouse strains. Single-cell RNA sequencing and metabolic analysis are used to identify developmental and disease-causing pathways. Stem cell-based methods for liver engineering are also used. As examples, the Peltz lab has produced mice with humanized livers that are used to improve drug safety; developed methods to engineer human liver from adipocyte stem cells; and to produce human liver organoids from iPSC, which are used for studying the pathogenesis of human genetic liver diseases.