11.   Environmentalists and other activist groups have long opposed efforts to add genes to foods.

12.   First, it adds a gene to the tumor cells.

13.   For prostate cancer, for example, scientists might add a gene that would kill prostate cells on command.

14.   If scientists can add genes to monkey embryos, it should be possible to add genes to human embryos, raising the emotionally fraught issue of human genetic engineering.

15.   If it is refined to be highly effective in monkeys, it could be just a short step to using it to add genes to human embryos.

16.   If researchers can alter living cells by adding new genes, then the cells could be sent into the body to carry out specific biological tasks.

17.   It did not study other common types of alterations, such as adding genes to make plants herbicide-resistant or to improve their vitamin content.

18.   It did not study other common types of alterations, such as adding genes to make plants herbicide-resistant or improve their vitamin content.

19.   Next, Wilmut expects to add genes to the cultured adult sheep cells to turn them into miniature factories churning out pharmacologically useful proteins.

20.   Once they had the fetal cells they grew them in the laboratory and added new genes, at least one of which was human.