For the first time, scientists have created embryos that are a mix of human and monkey cells. The embryos, described Thursday in the journal Cell, were created in part to try to find new ways to ...

Gleaning stem cells from cloned monkey embryos, as a team of Oregon researchers has done, is an impressive step. But it probably won't lead to medical treatments anytime soon. One hurdle is ethical ...

Early human development is a complex, multistep process that’s even more complicated to study in the lab. Models made from stem cells avoid some of the trouble with using real human embryos. In June, ...

In 2021, scientists grew human stem cells in a monkey embryo, creating a human-ape hybrid. Is this mad science? Is it immoral, even criminal? Or could creating hybrids now help us defeat disease?