CRISPR-Cas9 is a gene editing tool adapted from bacterial immune defenses. It's abilty to make quick, specific replacements of portions of the genome make it the one of the most popular techniques for gene editing. The first CRISPR sequences were discovered in 1987, but it wasn't until 2007 that scientists began to figure their purpose. In January of 2013, five seperate research teams all published articles about using the CRISPR-Cas9 system in gene editing. Since then, CRISPR has sparked a wave of interest in gene editing, both in scientists and to a lesser degree, the greater public.