The now-famous CRISPR technique traces its history back to 2012 when, during a study of bacterial immune systems, scientists demonstrated its ability to act as a gene-editing tool. The technique essentially uses a cell's own repair mechanism to fix cuts in certain locations on a DNA strand. A particular enzyme, Cas9, is directed to a target on the strand, where it then acts like a pair of scissors and cuts the DNA. From there, the targeted portion of the strand can be removed and, if necessary, replaced with another piece of DNA. Though CRISPR was by no means the first gene-editing technique to be invented, its predecessors were more complicated, expensive and time consuming. And few offered as many opportunities for broader application. Advancing at a Steady Pace After its inception in 2012, CRISPR technology improved rapidly, and its pace hasn't slowed.