My Uncle was asking me about the recent breakthrough in transforming adult skin cells into embryonic stem cells. Specifically, what is the role of retroviruses in performing the transformation.
To answer the query, I'm going to first direct you to pharyngula for a comprehensive summary of the latest article.
If you don't have time to wade through that posting, here's the short version:
The researchers have discovered the 'reset switch' for cells. This switch consists of four genes. To activate the switch, the researchers used retroviral transfection to insert multiple copies of these genes into a cell, along with 'promotors', which ensure that the genes are activated. As pharyngula explains, is not a particuraly elegant solution, but allows the researchers to demonstrate the effect of the genes. A better solution will involve a technique to activate the natural copies of the 'reset switch' genes already in the cell.
Retroviral transfection has been the foundation of gene therapy and other gentic research since the early 1990's. The technique itself is not new, just it's application.