Homologous Gene Targeting to Study ECM Assembly - Methods in Molecular Biology: Extracellular Matrix Protocols - page 177

2. Unlike electroporation and blastocyst injection, routine culturing of ES cells does

not need to achieve single-cell suspension after trypsinization.

3. The quality of the injection pipet is critical and particular attention should be

paid to the type of glass that is used, the way the end of the pipet is bent and the
dimension and sharpness of the tip.

4. Successful germ-line transmission is usually obtained with >60% chimerism. It

is, therefore, best to inject many independent ES clones several times in order to
identify those yielding the highest chimeras that will then be mated to test germ-
line transmission.

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