The Shigei Medical Research Institute, affiliated with the Shigei Medical Foundation in Okayama, Japan, is a multidisciplinary private research institute focused on medical science and biotechnology. With a legacy spanning nearly five decades, the institute is particularly active in renal disease research, including hereditary conditions such as Alport syndrome. It is also notable for its advancements in immunology, having developed high-specificity monoclonal antibodies used in diagnostic and research applications. One of its significant scientific contributions is the GONAD (Genome-editing via Oviductal Nucleic Acids Delivery) method—an innovative in vivo gene delivery system that allows CRISPR-based editing in mouse embryos without the need for ex vivo manipulation. Shigei continues to contribute to both applied biomedical research and fundamental life sciences.