Scott and Heather learn about CRISPR/Cas9, the hot new technique for editing genes. They talk to John Steele, a postdoctoral researcher in Larry Goldstein’s lab in the UC San Diego School of Medicine, about how CRISPR/Cas9 works and how he is using it and another leading-edge technique — induced pluripotent stem cells (iPSCs) — to study Alzheimer’s disease and other neurological disorders.