What Is The ‘Gene Scissor’ Tool And Why Did It Win A Nobel Prize?

By: Shrishaila, Diamond

Published On: November 26, 2021

The inventor and scientist, popularly remembered as the founder of Nobel Prizes - Alfred Nobel, envisioned a better tomorrow fueled by ideas and inventions that had the potential to change the world. Emmanuelle Charpentier and Jennifer A. Doudna of the University of California, Berkeley, did just that with their trailblazing work on the gene-editing tool CRISPR-Cas9. CRISPR-Cas9 won a Nobel Prize in chemistry owing to the revolutionary results it procured within the field of molecular biology.

So what is CRISPR-Cas9?

Cited as one of the most important scientific discoveries of this century - CRISPR-Cas9 (a.k.a clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9) is a method of genome editing. Genome editing or gene editing is understood to be a group of technologies allowing medical researchers to alter genetic material by inserting, replacing or deleting a specific DNA sequence in the genome. Currently, CRISPR-Cas9 is one of the core technologies being used to facilitate genome editing. 

CRISPR-Cas9 as a method of gene-editing (hence the name gene scissors) is considered to be faster, cheaper and more efficient than the other gene-editing approaches. 

OK - But What Does This Scientific Advancement Really Mean For Us?

CRISPR-Cas9 can help geneticists, medical researchers and scientists in the prevention and treatment of human diseases. It is adapted by a naturally occurring genome editing system in bacteria. These bacteria capture the DNA of invading viruses and use them to create CRISPR arrays. These arrays help the bacteria remember the viruses for when they attack again. The work of the CRISPR arrays is key here because it allows the bacteria to produce RNA segments from its arrays to target the attacking virus. The bacteria then use Cas9 or a similar enzyme to cut the DNA apart, which disables the virus. This exact system was observed and can now be recreated in a lab. To know more about how it was recreated, read here.

Like you must have already guessed, CRISPR-Cas9 can be used as a stepping stone to correct mutations, remove unwanted genes and tackle the ever-rising issue of rare genetic diseases. According to University of Gothenburg researcher, Anne Farewell, the time taken to identify certain types of cells will be reduced multi-folds. All in all, the gene scissors or the CRISPR-Cas9 mechanism speeds up the process with much more precision as compared to traditional methods of editing genes. 

According to a report in Wipo.Int, the singling out method can be revolutionary in beating sickle cell diseases such as β-thalassemia. The same report also revealed that the CRISPR-Cas9 was given to someone diagnosed with LCA10, a rare disease that has very few to no known treatments available. LCA10 causes blindness at a young age, however, the gene scissor tool was used to remove the mutated gene - CEP20 - in this situation. Similarly, CRISPR Cas9 can be used to edit strands of DNA that have abruptly mutated.

As mentioned above the gene scissor tool is already being explored in research in a wide range of diseases including but not limited to cystic fibrosis and sickle cell diseases. Moreover, it also holds the potential to cover more complex diseases such as cancer, heart diseases and mental illness in the future.

The mechanism by which CRISPR-Cas9 recognizes and targets DNA for cleavage. Image Source: Nobelprize.org.

In conclusion - 

CRISPR-Cas9 has opened endless possibilities in not just the healthcare industry and human medicine field but also biofuels and agriculture. So far gene editing studies on humans are still relatively rare and highly regulated. With high precision and quite literal DNA-altering technology, we wait to see what the future holds for humankind.

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