2015's biggest breakthrough could deliver designer babies

Aired: 12/30/2015 | 0:09:15 | Clip
CRISPR, a new method for editing genes, has been called a development that could revolutionize medicine. Cheaper and more precise than past gene editing, this promising tool has also raised concerns. Gwen Ifill talks to Jennifer Doudna of University of California, Berkeley and Paul Knoepfler of University of California, Davis.