Precision engineering

时间:2019-03-06 07:07:12166网络整理admin

Cloning could make the genetic engineering of animals far less hit-or-miss. Until now, most mammals could be modified only by injecting DNA into fertilised eggs. The DNA would then integrate into the animal’s genome at random, with uncertain results. A team led by Kenneth McCreath at PPL Therapeutics near Edinburgh describes in this week’s Nature how they first grew adult sheep cells in culture and made precise changes to targeted parts of the sheep genome. Then they cloned the altered cells by fusing them with egg cells from which the nuclei had been removed,