The project is focused on developing efficient strategies to modify the genome of human embryonic stem cells (hESCs). Such modifications are likely to be essential for the full therapeutic potential of hESCs to be realized because they will allow for precise changes to be made in the hESC genome (without unwanted or unanticipated effects on the genome). Therapeutic changes made to the hESC genome could include those that correct inherited diseases, or those that augment the functions of critical genes that can confer a needed therapeutic effect. hESCs carrying changes of this sort can eventually be used in transplant settings to alleviate or cure diseases. The strategies favored by this project (those that depend on homologous recombination) have been widely exploited in model systems, but have yet to be optimized for use with hESCs. Various approaches will be tested in the project to optimize homologous recombination procedures for hESC genome modification. The cell lines generated in this project, the methodological expertise acquired, and the DNA reagents should all help to facilitate future efforts to generate hESCs carrying therapeutic mutations.
The expertise we hope to gain in this project is essential for future projects that depend on generating precise changes in the human embryonic stem cell (hESC) genome. As has been the case with other experimental systems, once established, the technique of gene targeting by homologous recombination should be widely exploited for research and ultimately for therapeutic purposes. The State of California will benefit from this project because it will provide a means for realizing the full therapeutic and research potential that hESCs embody. Engineering specific changes into the hESC genome will allow for genes that cause disease to be corrected prior to the use of hESCs in transplant settings. It will also make a critical experimental tool available to researchers so that they can further understand biology of hESCs and thus make better use of the cells in therapeutic contexts.