Some mothers do 'ave 'em: Mice with two mums bred in China
Researchers unlock some of the mysteries of reproduction in an experiment that created healthy mouse pups from two female sources

Scientists in Shanghai are rewriting the rules of reproduction with a groundbreaking experiment that combined genetic material from two female mice to create healthy offspring, according to a paper in Cell Research on Tuesday.
But the researchers said they strongly opposed using the technology to create humans, saying it would give rise to serious ethical and genetic problems.
The team, led by Professor Li Jinsong from the Chinese Academy of Sciences’ Institute of Biochemistry and Cell Biology, genetically modified ovum-derived embryonic stem cells to make them function like sperm, and injected the cells into ova to produce a batch of mouse pups with two genetic mothers.
“The entire process does not require any male involvement,” Li said.
“Sperm is replaceable – that’s clear from the experiment.
“All we need are a pair of eggs, and from these eggs we can create a family, a colony, even a kingdom of healthy pups.”