Table 1.

Rat models and knockout technologies

Preferred research areas for gene-modified rat models
Knockout rats will enable research in areas where they are the proven model organism of choice. This includes many aspects of:
Metabolic and cardiovascular diseases
Toxicology screening and drug tests
Behavioral and learning studies
Knockout technologies for the rat
ES cells are the tool of choice for creating knockout or knock-in animals and have now been derived for the rat
ZFNs use zinc-finger proteins associated with the DNA-cleaving domain of a restriction endonuclease to target a specific locus in the genome, in order to cause a double-strand break. Currently, this is the most tractable method for creating knockout rats
Genetic mutation in SSCs may eventually allow for 100% germline transmission, but these cells have not yet been used successfully to create knockouts
Transposon-tagged mutagenesis and ENU sperm archives facilitate cost-efficient generation of knockout rats using a non gene-targeted approach; the latter technique also produces interesting allelic variants that often resemble human alleles