CRISPR-Cas9 is a genome editing system. CRISPR systems provides immunity to bacteria and archaea from viruses and has been adapted for use as a genome editing tool capable of knocking out genes and rewriting genetic sequences in animal, plant and fungi. CRISPR-Cas9 is being adapted to other applications outside genome editing.
Horvath and Barrangou teamed up with Virginjus Siksnys at Vilnius University, Lithuania and they published how CRISPR works with Cas9 in 2012 . Around the same time UC Berkeley’s Jennifer DoudnaJennifer Doudna and Emmanuelle Charpentier now at the Max Planck Institute for Infection Biology, Berlin also described in Science how Cas9 works in the CRISPR system . Because they also engineered a simpler version of CRISPR that could likely to work in other organisms including human cells , this transformed this bacterial immune function into a usable biotechnology tool.