The discovery of crispr cas9

by Seran Gemechu

CRISPR/Cas9 is a simple but powerful gene-editing technology that we can harness to precisely modify, delete or correct disease-causing abnormalities at their genetic sources. “CRISPR” refers to Clustered Regularly Interspaced Short Palindromic Repeats of genetic information, which some bacterial species use as an antiviral mechanism in combination with the Cas9 enzyme. Cas9 – a CRISPR-Associated endonuclease – acts as “molecular scissors” to cut DNA at a specific location. The location at which Cas9 cuts DNA is specified by a guide RNA comprised of a crRNA component and a tracrRNA component, either individually or combined together as a single guide RNA (sgRNA). For uses in therapeutic gene editing, a guide RNA can direct the molecular scissors to cut the DNA at the exact site of the mutation present in the genome of patients with a particular genetic disease. Once the molecular scissors make a cut in the DNA, the cell’s own robust natural repair machinery repairs the cut, a process that can disrupt or delete a disease-causing gene, or correct that gene if the desired DNA is added as a template. Dr. Emmanuelle Charpentier, one of CRISPR Therapeutics’ scientific founders, co-invented the application of CRISPR/Cas9 in gene editing.