The Nobel Prize in Chemistry 2020 was awarded jointly to Prof. Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens in Berlin, Germany and Prof. Jennifer A. Doudna of the University of California in Berkeley, USA “for the development of a method for genome editing.” They have discovered one of gene technology’s sharpest tools: the CRISPR/Cas9 genetic scissors. Using these, researchers can change the DNA of animals, plants and microorganisms with extremely high precision. This technology has had a revolutionary impact on the life sciences, is contributing to new cancer therapies and may make the dream of curing inherited diseases come true.
With the discovery of the RNA-guided CRISPR-Cas9 system, an easy and effective method for genome engineering has now become a reality. The development of this technology has enabled scientists to modify DNA sequences in a wide range of cells and organisms. Genomic manipulations are no longer an experimental bottleneck. Today, CRISPR-Cas9 technology is used widely in basic science, biotechnology and in the development of future therapeutics.
Researchers need to modify genes in cells and this used to be time-consuming, difficult and sometimes impossible work. Using the CRISPR/Cas9 genetic scissors, it is now possible to change the code over the course of a few weeks.
As so often in science, the discovery of these genetic scissors was unexpected. During Emmanuelle Charpentier’s studies of Streptococcus pyogenes, one of the bacteria that cause the most harm to humanity, she discovered a previously unknown molecule, tracrRNA. Her work showed that tracrRNA is part of bacteria’s ancient immune system, CRISPR/Cas, that disarms viruses by cleaving their DNA.
Charpentier published her discovery in 2011. The same year, she initiated a collaboration with Jennifer Doudna, an experienced biochemist with vast knowledge of RNA. Together, they succeeded in recreating the bacteria’s genetic scissors in a test tube and simplifying the scissors’ molecular components, so they were easier to use.
In an epoch-making experiment, they then reprogrammed the genetic scissors. In their natural form, the scissors recognise DNA from viruses, but Charpentier and Doudna proved that they could be controlled so that they can cut any DNA molecule at a predetermined site. Where the DNA is cut, it is then easy to rewrite the code.
Since Charpentier and Doudna discovered the CRISPR/Cas9 genetic scissors in 2012 their use has exploded. This tool has contributed to many important discoveries in basic research. In medicine, clinical trials of new cancer therapies are underway, and the dream of being able to cure inherited diseases is about to come true. These genetic scissors have taken the life sciences into a new epoch and, in many ways, are bringing the greatest benefit to humankind.
The power of the CRISPR-Cas9 technology also raises serious ethical and societal issues. It is of utmost importance that the technology is carefully regulated and used in responsible manner. To this end, the World Health Organization has recently established a global multi-disciplinary expert panel to examine the scientific, ethical, social and legal challenges associated with human genome editing, with the aim to develop a global governance framework for human genome editing.