Objections to the immorality of genome editing?

After a Chinese scientist announced this week the birth of twin girls whose DNA he had altered many months earlier when they were microscopic, single-cell embryos, condemnation of this previously secret experiment was swift and absolute. Scientists and ethicists from around the world called it “premature” and “irresponsible.”

The majority of this criticism is motivated by major concerns about safety — we simply do not yet know enough about the impact of CRISPR-Cas9, the powerful new gene-editing tool, to use it create children. But there’s a second, equally pressing concern mixed into many of these condemnations: that gene-editing human eggs, sperm, or embryos is morally wrong.

That moral claim may prove more difficult to resolve than the safety questions, because altering the genomes of future persons — especially in ways that can be passed on generation after generation — goes against international declarations and conventions, national laws, and the ethics codes of many scientific organizations. It also just feels wrong to many people, akin to playing God.