Chinese scientists say they have bred healthy mice from 2 females. Researchers at the Chinese Academy of Sciences say they used a new type of gene editing technology to breed healthy mice from 2 mothers. Their new study says 29 mice were produced that are "bi-maternal." Mice produced from 2 fathers, however, survived only a couple of days. The genetic editing has raised ethical questions with scientists who say the use of it on humans could effect the gene pool in future generations and have unintended consequences.