As creator of ‘CRISPR babies’ nears release from prison, where does embryo editing stand?

Biophysicist He Jiankui, having served a 3-year sentence for creating the world’s first genetically engineered babies, may be released from a Chinese prison this week, Science has learned. He’s largely secret use of the genome editor CRISPR to alter the DNA of human embryos and implant them into two women led to three births, sparking ethical outrage and fears for the babies’ health (about which little is known). It did not, however, bring an end to basic research on human embryo editing.

The response to He’s November 2018 announcement was “severe and vibrant,” says Fyodor Urnov, who studies CRISPR-based genome editing at the University of California, Berkeley. For now, Urnov sees no circumstance that would justify efforts to genetically modify babies. But he strongly supports using CRISPR to fix disease-causing mutations after birth, without causing heritable changes to a human genome, and regrets that “we have poured a jar of tar on gene editing.” And Urnov and others believe that, used responsibly and safely, embryo editing could eventually prove a powerful tool against disease in rare circumstances. In laboratory studies...