Ethicist: Gene-editing human embryos 'a train wreck of a thing to do'

The revelation in late November that a Chinese researcher had edited genes in human embryos and then implanted them in a woman was "a train wreck of a thing to do," said an ethicist at the National Catholic Bioethics Center in Philadelphia.

"Normally clinical research proceeds in phases. First, you verify it works in animals, etc. Second, you verify that it's safe. In small things you verify it's effective," said John Brehany, the center's director of institutional relations. "He skipped all that stuff."