KO first model, also called conditional ready model, is a multipurpose mouse model generated with a modified conditional knock-out strategy. This time-saving strategy makes it possible to obtain a reporter gene knock-in model and conditional knock-out models simultaneously from a single project by breeding with the Cre/LoxP recombination system or Flp/FRT recombination system.https://www.creative-biolabs.com/drug-discovery/therapeutics/ko-first-conditional-ready-models.htm