Fourth-generation pig cloned

TOKYO (AP) - A Japanese geneticist said Wednesday his research team created the world's first fourth-generation cloned pig, an achievement that could help scientists in medical and other research.
The male pig was born at Tokyo's Meiji University in July, said Hiroshi Nagashima, the geneticist at the university who led the project.
Earlier attempts to clone animals for several generations were problematic. Scientists had thought that was because the genetic material in the nucleus of the donor cell degraded with each successive generation, Nagashima said.
But the team's findings show that a large mammal can be cloned for multiple generations — in this case, the clone of a clone of a clone of a clone — without degradation, he said, while acknowledging that mice have already been successively cloned for multiple generations.