Cloning as an 'enabling experiment'; Identity of tantalizing cell remains hidden
As the rest of the world speculates about what the cloning of a single sheep may mean for humanity, the exclusive licensee to aspects of the technology responsible for this feat is working toward its ultimate goal - developing a commercially useful animal from a genetically altered adult cell.
PPL Therapeutics plc (LSE: PTH.L, Roslin, Scotland) produces human therapeutic proteins in the milk of transgenic sheep and cows by adding genes to their genomes. According to Research Director Alan Colman, when the company became interested in nuclear transfer technology, it wanted a technique that instead would allow it to remove specific genes from the genomes of large mammals
Knockouts have been accomplished in rodents but never in larger mammals, and the company viewed this as a shortfall of existing transgenic techniques. It