PROJECT SUMMARY The Animal Modeling Core (AMC) of the University of Michigan Skin Biology and Diseases Resource-based Center (UM-SBDRC) serves as a critical shared resource that facilitates the design, development, and characterization of mouse models aimed at gaining deeper insight into skin biology and disease, significantly advancing the overall goals of our Center and the NIAMS mission. Genetically-engineered mouse models (GEMMs) provide a powerful tool for testing hypotheses that emerge from the sophisticated sequencing and gene editing studies driven by the Functional Analytics Core (FAC), extending them to the physiologically relevant setting of an intact organism. Although many GEMMs are available, new project-specific models are frequently needed. However, there are major impediments to successful new mouse model development and characterization, including the significant time investment and cost needed to acquire detailed empirical knowledge and expertise to be consistently successful. In addition, commercial GEMM development is frequently suboptimal and costly. The continued long-term goal of the AMC is to override these and other obstacles for Center Members by offering comprehensive GEMM services for skin-related studies through the following aims: 1) provide hands-on support for the design and development of new GEMMs and proper use of existing mouse models; 2) provide training for consistent and reproducible in vivo GEMM manipulation; and 3) provide detailed instruction and assistance for conducting comprehensive GEMM phenotyping. The work performed with AMC support during the current grant period has greatly benefitted Center Members by advancing their skin-relevant research leading to impactful publications, collaborations, and grants. Given the complex interplay of multiple cell types that is best studied in an intact organism, rigorous mouse modeling remains critically important as a powerful tool for understanding the pathogenesis of skin disease and as an engine for producing pre-clinical disease models that should ultimately lead to much-needed new therapies.