Hybrid Human-Chicken Embryos Illuminate Key Developmental Milestone

May 24, 2018

(Nature) – Before a cluster of cells can develop into an embryo, it must first decide which end is up. But that process had never been observed in humans — until now. For the first time, researchers have watched human ‘organizer’ cells direct the formation of an embryo’s top, bottom, front and back. They did so by developing a technique that sidesteps restrictions on research with human embryos by grafting human cells onto chicken embryos. The method, published on 23 May in Nature, could supplant the use of human embryos in some laboratory experiments.