The present invention provides a novel vector system and thereby a novel method
for the simplified construction of recombinant vectors for directed mutagenesis.
Said vector system is used to modify the eukaryotic genome, particularly of embryonic
stem cells, at precise and predefined loci by the means of homologous recombination.
Furthermore, said system finds its usage in the generation of new strategies for
gene therapy and in the generation of genetically modified higher eukaryotic organisms.
