Animal models for human disease play an important role in understanding the causes and mechanisms of genetic disorders and are invaluable in developing new treatments and therapeutics. These animals are produced by several techniques, including transgene insertion and targeted gene knockout in embryos to generate new lines, but the subsequent crossbreeding and necessary genotyping make these time-consuming strategies. The generation of embryonic stem cell lines from genetically engineered embryos combined with somatic cell nuclear transfer (SCNT) is routinely used to produce animal clones with a known genotype from which further stocks can be bred and has been used with success in the production of sheep and mice. However, the production of cloned rats has been unsuccessful due to technical difficulties associated with spontaneous oocyte activation that occurs within an hour of egg collection.
In the September 25