Choice of Mouse Strains for Gene Targeting

In designing and planning the generation of a gene-targeted mouse, there are several stages at which the choice of mouse strain is critical. Consideration must be given to the genetic strain from which (1) the genomic DNA library, (2) the embryonic stem cells, and (3) the recipient embryos are derived, in addition to (4) the strain with which the chimaeric mice are mated. Ultimately, only the strain of genomic DNA, the (ES) cell strain, and the strain of mice for mating contribute to the genetic composition of the targeted mouse, whereas the strain of host embryos is only relevant in that it must be compatible with the choice of ES cells, otherwise the ability of the chimeric mice to provide germline transmission of the ES cell genome may be compromised.