The slippery slope of the human gene editing debate

The ethical debate about what is now called “human gene editing” (HGE) began sixty years ago. At the time, eugenicist scientists wanted to use new knowledge about the structure of DNA to modify humans—to perfect the human species by making us more healthy, musical, intelligent, and generally virtuous. A consensus later formed that gene editing on individuals to remove disease is acceptable, but nobody should try to change the human species. This is known as the somatic (individual) vs. germline (species) distinction, and it served as a moral limit on HGE for 50 years. A few years ago the news broke that a Chinese scientist had facilitated the creation of children who have been genetically modified so their descendants would also be modified—germline HGE. The germline limit now seems to be gone. Are there any limits left?

The HGE debate, like many bioethical debates, is set up like a slippery slope. At the top is an act universally considered morally virtuous (point A). Stepping on the slope at the top makes the act a little bit further down the slope...