Cloning of six calves makes identical herd a reality

Scientists have successfully cloned six calves from a bull's ear using skin cells that were grown in a laboratory for three months.

Scientists have successfully cloned six calves from a bull's ear using skin cells that were grown in a laboratory for three months.

The technique of cloning from cultured cells - a marked departure from previous cloning experiments - means it is now practical to produce an identical herd of genetically modified animals from an individual. Culturing cells for up to three months allows scientists to carry out highly specific changes to the genetic material that will be inherited by future offspring of the clones.

The breakthrough means that it will now be possible to perform virtually unlimited modifications to the genes of cattle, and other farm animals, which were previously limited to laboratory mice. It also raises the prospect of being able to carry out similar alterations to human cells before cloning. The ear cells came from a 17-year-old Japanese black bull. The scientists said the procedure shows there is no technical barriers to cloning from an old, male animal.

The research was carried out by Xiangzhong Yang, of the University of Connecticut, andthe Kagoshima Prefectural Cattle Breeding Development Institute in Japan.

"The findings are novel and unexpected," said Dr Yang.