For the first time in history, the Chemistry Nobel Prize has been jointly awarded to Professors Emmanuelle Charpentier and Jennifer Doudna, for their discovery of the CRIPSR – Cas9 “genetic scissors”. A way of making specific and precise changes to DNA in living cells, this technology on gene editing is significant: it is a tool for rewriting the code of life.  

In Prof Charpentier’s studies of the bacterium Streptococcus pyogenes, she discovered tracrRNA,  a mechanism essential in the function of CRISPR – Cas9, which disarms viruses by cleaving DNA like scissors. After publishing her findings in 2011, Prof Charpentier and Prof Doudna began their collaboration. They amplified the bacterium’s genetic scissors in a test tube and simplified their molecular components for more accessibility. In their natural form, the genetic scissors recognise DNA from viruses. However, the professors showed that they could be reprogrammed to cut any DNA molecule at a predetermined site. Like a biological ‘find and replace’ function, the Cas9 enzyme is guided to a specific location by guide RNA and cuts the two strands of DNA.  

Transformative for basic research, crucial to clinical trials of new cancer therapies and having the potential to treat or cure inherited diseases, CRIPSR – Cas9 has a myriad of uses. Due to this discovery, personalised medicine could one day be a normalised occurrence. However, as with all gene therapies, there is always an ethical minefield around the possibility of using the mechanism to create “designer babies". With detailed and strict regulation and enforcement, the potential of CRISPR – Cas9 could be limitless.