Cas9

CRISPR gene editing tested in a human for the first time

A Chinese group of scientists has become the first to inject a person with edited genes using the revolutionary and still controversial CRISPR-Cas9 technique. Key points: CRISPR-Cas9 can trim away unwanted parts of the genome A protein that slows down the cell's immune response was trimmed out of the DNA The edited DNA was cultivated and injected back into the patient A patient with aggressive lung cancer received the modified cells as part of a clinical trial at the West China Hospital in Chengdu.

The gene editor CRISPR won’t fully fix sick people anytime soon. Here’s why

This week, scientists will gather in Washington, D.C., for an annual meeting devoted to gene therapy—a long-struggling field that has clawed its way back to respectability with a string of promising results in small clinical trials. Now, many believe the powerful new gene-editing technology known as CRISPR will add to gene therapy’s newfound momentum. But is CRISPR really ready for prime time? Science explores the promise—and peril—of the new technology.

How does CRISPR work?