When Chinese researcher He Jiankui revealed that he had edited the embryos of twin girls to protect them from HIV, it triggered an international uproar. Critics said he had crossed a red line. Now Denis Rebrikov, a geneticist in Moscow, wants to edit embryos of a deaf couple to prevent them from passing on the mutation that compromised their hearing. Unlike He, Rebrikov is open about his plans, seeking high-level regulatory approval, and addressing the critics head on. Pulitzer Center grantee Jon Cohen traveled to Russia to meet with Rebrikov, the couple, bioethicists, geneticists, and Ministry of Health officials.
