Evaluation of technical approaches to pronuclei injection
The transgenic technology makes it possible to introduce specific genetic alterations into the genome of all cells in an organism. This has opened entirely new possibilities to analyse the regulation and function of individual genes in a living animal. We have established a facility for the production of transgenic mice and have generated 37 different transgenic mouse strains. Here we analyse if the frequency of transgenic offspring correlates with the length of the introduced transgene and/or with the genetic background of the injected eggs. Our data suggest that the transgenic frequency is relatively independent of the length of the construct. The genetic background is more important and we find that specific steps in the process of generating transgenic mice are considerably more efficient in an F2 intercross between C57BL6 and CBA than in inbred C57BL6 mice. Finally we discuss how we have used the transgenic technology to analyse the regulation and function of genes in
the developing nervous system.