An arms race is playing out inside your body. It’s part of an invisible war that’s raged for billions of years. When viruses hunt and infect bacteria, the bacterial survivors store pieces of their vanquished foes — DNA snippets — within their genomes so that next time, they can detect and defend against the attack. In response, viruses evolve their own counterattack.
The bacteria’s natural defense system is called CRISPR-Cas9. And in 2012, biochemist Jennifer Doudna, together with French microbiologist Emmanuelle Charpentier, upended genetics with an ingenious idea. What if scientists could exploit CRISPR as a gene-editing tool? Since then, Doudna and others have hacked these cellular weapons in an effort to treat diseases and create stronger crops. Now scientists are attempting another task: avoiding unintended mutations resulting from their gene edits.
