Science
CRISPR 3.0: The Gene-Editing Revolution That's Quietly Changing Medicine
In December 2023, the FDA approved Casgevy — the first CRISPR-based therapy for a human disease. It works in a single treatment session: a patient's stem cells are removed, their DNA edited, and the corrected cells returned. The results in sickle cell disease trials were striking. But Casgevy uses first-generation CRISPR, which cuts DNA like scissors. A newer class of tools — base editing and prime editing — can rewrite individual letters of the genetic code without cutting the double helix at all, dramatically reducing the risk of unintended edits. Clinical trials of these next-generation systems began in 2024. The field is not waiting for the conversation to catch up.