CRISPR-Cas9 Is a Powerful New Gene-Editing Technique

A relatively new gene editing technology called CRISPR-Cas9 already is affecting basic biological research profoundly and holds promise for treating human disease. In three recent papers, researchers report advances and grounds for concern.

A team from MIT and Harvard reported a modification of the CRISPR technique that could escalate its potential for editing genes in living animals. The team targeted the pcsk9 gene, which is important in cholesterol metabolism and is inhibited by a new class of drugs (NEJM JW Gen Med May 1 2015 and N Engl J Med 2015 Mar 15; [e-pub]). About 40% of hepatocytes in living mice contained the edited gene, leading to prompt and marked reductions in total cholesterol. The gene editing apparently did not induce any…