The 2020 Nobel Prize in Chemistry has gone to Emmanuelle Charpentier and Jennifer A. Doudna “for the development of a method for genome editing.” That method, formally known as CRISPR-Cas9 gene editing but often called simply CRISPR, allows scientists to precisely cut any strand of DNA they wish. In the 8 years since its creation, CRISPR has been a boon for biologists, who have published thousands of studies showing that the tool can alter DNA in organisms across the tree of life, including butterflies, mushrooms, tomatoes, and even humans.
“The number of discoveries in biomedicine that have had the impact that Jennifer’s and Emmanuelle’s had can be counted on the fingers of one hand: recombinant DNA, PCR [polymerase chain reaction], DNA sequencing, and now CRISPR,” says Fyodor Urnov, a gene-editing scientist at the University of California, Berkeley. “We have never had a technology as powerful and versatile as genome editing with CRISPR.”
Charpentier, who is now at the Max Planck Unit for the Science of Pathogens, and Doudna, at UC Berkeley, began working together in 2011. The two scientists were inspired by a little-studied bacterial immune system that uses an enzyme called Cas9 to chop up the genes of invading viruses, which are saved as molecular mug shots. In 2011, Charpentier worked out the details of how a pair of bacterial RNA molecules controlled this process (Nature 2011, DOI: 10.1038/nature09886).
The two scientists began thinking about how they could rework this viral defense system into an easily programmable gene-editing tool. They synthesized a new molecule, called the single-guide RNA, which combines key features of the two bacterial RNAs and directs Cas9 to cut a specific site in DNA (Science 2012, DOI: 10.1126/science.1225829).
It was the tool that scientists had been waiting for. CRISPR is cheaper, faster, and easier to use than previous gene-editing tools. Academic labs quickly adopted the technique. Today, scientists can order Cas9 and custom guide RNAs at the click of a button. CRISPR opened up gene editing to the masses.
Charpentier, Doudna, and many others have founded biotech companies to apply CRISPR to agriculture and medicine. A few firms have already begun testing experimental therapies that use CRISPR to treat, and potentially cure, rare genetic diseases and cancer in humans.
“It’s wonderful to see Jennifer and Emmanuelle recognized in this way,” says David Liu, a CRISPR scientist at Broad Institute of MIT and Harvard. “With new treatments for human genetic diseases already in patients, with early positive outcomes, the era of human genome editing has already begun, and Emmanuelle and Jennifer are two of the key pioneers responsible for initiating this new era."