Cloned bull is cloned

Associated Press


SAN FRANCISCO - A clone of a cloned prized bull thrives today on a Japanese farm, living proof that "serial cloning" can successfully create life beyond mice.
The second-generation cloning that created the black bull named Kamitakafuku took place in 2000, but wasn't announced until Sunday because researchers wanted to ensure the bull matured and was healthy. The only other mammal known to have been cloned from a clone are mice.

"We have proven that recloning can be done in higher species," said University of Connecticut researcher Xiangzhong "Jerry" Yang, one of three authors of the study. The results appeared online Sunday in the journal Nature Biotechnology.

Yang and his colleagues "fused" 358 eggs to yield the single bull.

Still, cloning experts such as Jose Cibelli at Michigan State University said Yang's experiments offered evidence that a key mechanism thought to influence the aging process, called telomeres, is rewound in the cloned offspring.

Cibelli and others speculated the difficulty Yang had in recloning a single bull may magnify the genetic programming errors that many believe explain why so many cloned animals of all types die early, either as fe-tuses or newborns.