Fighting viruses with viruses? ‘Gene drive’ offers new strategy to beat infections

If your immune system or drugs can’t stop a viral infection, why not pit a virus against itself? That’s the provocative idea several labs are pursuing. They are studying whether deliberately introducing engineered viruses into people infected with their natural relatives can “drive” a foreign gene into those viruses that ultimately wipes out an infection. No lab has knocked down an infection in animals this way yet, but a group has now shown it’s theoretically possible. These so-called gene drives harness the genome editor CRISPR to perform genetic surgery that speeds the spread of a gene through progeny. So far, scientists have received the most attention for adding gene drives to animals such as rodents and mosquitoes to control their numbers. But in a preprint last week, the team reported a similar feat with herpesvirus-1 (HSV-1). When both engineered and unmodified herpesviruses were inoculated into mice, the gene drive converted up to...