One of the biggest mysteries of human life is how we develop from a tiny ball of cells into a being with bones, muscle and organs. The process starts inside the mother’s womb shortly after conception, but legal and regulatory restrictions on research involving human embryonic tissue have stymied scientists’ efforts to explain the process.
Now scientists have found a workaround. By transplanting human embryonic cells onto chicken embryos, researchers at Rockefeller University in New York City have created a hybrid embryo that they say will bring insights into fetal development — and perhaps lead to new cures for several diseases — without bumping up against the so-called “14-day rule” that prohibits research on human embryos more than two weeks old.
The popular media blasted the interspecies mash-up, with one headline reading “Half human-half chicken abomination created in US lab," even though no one is talking about creating a race of human-chicken beings. And the scientists defend their work, saying the hybrid embryo will help them understand why some human cells grow into the brain and nervous system, for example, while others form the trunk and limbs.