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.
There is a patent dispute over the invention of CRISPR-Cas9 technology specifically for use in human cells, between Doudna’s research team and Feng Zhang’s group at the Broad Institute (MITMIT and Harvard) . Zhang’s research group and George Church’s lab at Harvard Medical School, each published Science papers in 2013 showing they had modified CRISPR-Cas9 to edit the genome in human and mouse cells . The Broad Institute’s US patent, the first of several for mammalian use of CRISPR, is under appeal . Citing lack of novelty, the European patent office has revoked the first patent obtained by the Broad Institute and has granted patents to the University of California and University of Vienna . The first is for using the CRISPR-Cas9 system across prokaryotic and eukaryotic systems and the second is for a modified form of CRISPR-Cas9 to regulate gene expression.