In a breakthrough new study, scientists have created human-monkey chimera embryos for the first time. These chimeras pave the way for more accurate models of human biology and disease, which could open up a range of new medical benefits. But of course they also raise some complicated ethical concerns.
A chimera is, put simply, an organism that contains cells from more than one individual. It can occur naturally during development, such as when non-identical twins merge early on, or it can be an artificial process – technically, organ transplants create chimeras.
But it doesn’t necessarily need to be cells from the same species. Scientists have been experimenting with interspecies chimeras for decades, merging similar animals like mice and rats, and sheep and goats. And in the new study, researchers from the Salk Institute and Kunming University of Science and Technology successfully created chimeras of humans and monkeys.