NCB generates, shares, and archives mouse and rat models. We provide one-stop genetic modification service from tailor-made gene construction, strain production to animal breeding. Other than CRISPR/Cas9 genome editing technique, our center has unique bacterial artificial chromosome (BAC) technique to achieve large DNA fragment construction and insertion (~300 kb) for GM rodent production. We provide customized transgenic services as well as generate novel disease mouse models, humanized mouse models, and many useful tool mice, from multi-fluorescence to tissue-specific strains in different genetic backgrounds. Rodent Model Resource Center-NCB (RMRC) is a member International Mouse Strain Resource (IMSR) that facilitates sharing of valuable experimental animals.