This undated photo provided by researcher Katsuhiko Hayashi shows an adult mouse, which was born from an egg cell produced from a skin cell, and her pups, which were born normally. The eggs were produced by making skin cells revert to a kind of blank slate, so they could be prodded to develop into immature egg cells. The new work was reported online Oct. 3, 2012, in the journal Science by a team at Kyoto University. (Associated Press/Science, Katsuhiko Hayashi)

Photo by: Uncredited

This undated photo provided by researcher Katsuhiko Hayashi shows an adult mouse, which was born from an egg cell produced from a skin cell, and her pups, which were born normally. The eggs were produced by making skin cells revert to a kind of blank slate, so they could be prodded to develop into immature egg cells. The new work was reported online Oct. 3, 2012, in the journal Science by a team at Kyoto University. (Associated Press/Science, Katsuhiko Hayashi)