The stem cells, derived from human umbilical cord - blood and coaxed into an embryonic - like state, were grown without the conventional use of viruses, which can mutate genes and initiate cancers, according to the scientists. (sciencedaily.com)
What Renner's Aaron Cross has been subjected to is a programme involving use of viruses to deliver gene - enhancing chemicals into the body. (indianexpress.com)
One of the key caveats at the time, however, was that the technique required the use of a virus to introduce several genes into the skin (or other) cell, and these would remain in the cell, and so might contaminate the resulting stem cell or create cancer risks. (firstthings.com)