A Japanese geneticist confirmed on Wednesday that his research team had created the world's first fourth-generation cloned piglets, an achievement he says could help scientists find cures for diseases that affect human beings.
Hiroshi Nagashima, the geneticist at the university who led the project, said the three male piglets were born at Tokyo's Meiji University on July 23.
Nagashima said that one of the piglets died shortly after birth but added that the death had nothing to do with the piglet being cloned and it was common for one or two to die in a litter of piglets.
Earlier attempts to clone animals for several generations had been problematic, he said.
Scientists had thought that was because the genetic material in the nucleus of the donor cell degraded with each successive generation, Nagashima explained.
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.
US researchers had earlier cloned sixth-generation mice.
The professor said however that his project was more useful as a pig is far more similar to a human being than a mouse.
Nagashima said that he was confident this research could pave the way to finding new cures for diseases that affect humans.
"We can apply the similar treatment to cure the disease and operation method for humans to pigs as the size of their bodies are similar. So, it (cloning pigs) will be helpful to study the diseases and cures for human beings," Nagashima said.
A geneticist with the government-affiliated Agriculture, Forestry and Fisheries Research Council (AFFRC), said the results may prove important to breeders of other large animals, such as racehorses or bulls, looking for ways to keep a prized animal in the gene pool.