About mouse production
Each center has their own internal processes for mouse production, but these can be combined into a few categories. Centers have historically used ES cells as the starting point of the production process, but are transitioning more towards the CRISPR methods to produce the mice. The production numbers reflecting the project status are available on iMits for production using ES cells and GenTaR for production using CRISPR.
Please see the IMPC procution paper: A resource of targeted mutant mouse lines for 5,061 genes, Nature Genetics 2021.