In celebration of February 11, International Day of Women and Girls in Science

In light of the International Day of Women and Girls in Science celebration, read here the winners of the Nobel Prize in Chemistry in 2020, Dr. Emmanuelle M. Charpentier and Dr. Jennifer A. Doudna, and their discovery of CRISPR/Cas9 genetic scissors.

The 2020 Chemistry Nobel prize was awarded to two women scientists, Emmanuelle M. Charpentier and Jennifer A. Doudna, for their breakthrough discovery of genetic scissors, a tool to edit the genome using the CRISPR/Cas9 technology. Considered as one of the most important scientific developments of this century, their method of editing an organism’s DNA allows advances in many scientific fields, ranging from Agriculture to Human Health and Medicine, thus raising hopes of eventually being used for correcting pathogenic changes in the DNA and curing genetic diseases. This Nobel prize was the first science prize shared by two women scientists exclusively.

Everything started from bacteria

The idea behind this novel gene editing approach is adapted from the bacteria’s defensive system. The natural CRISPR/Cas system found in bacteria can disable the virus by cutting the viral genome (DNA/RNA) during an infection, and insert them on their own genome for their protection in case of future attacks. The CRISPR/Cas9 system acts through specific parts of the DNA that guide towards the targeted region and are known as CRISPR; and Cas9, an enzyme that acts as scissors allowing specific and precise cuts to the targeted region. Through the work of Charpentier and Doudna, the CRISPR technology was modified and adapted into a system that could find and either edit, delete or add a specific part of DNA inside the cells – such as the part with the genetic mutation – thereby correcting it.

When two women join forces

The breakthrough discovery emerged from a collaboration of the two scientists. Charpentier initially discovered an unknown component of the CRISPR/Cas system in bacteria Streptococcus pyogenes. After this initial discovery, Charpentier collaborated with Doudna to develop a simple gene-editing tool based on Charpentier’s previous findings. The results were published in 2012 in the Journal of Science, in which they successfullygenerated a simpler, easier, more efficient and more cost-effective tool compared to previous genome-editing technologies. As such, these characteristics opened the doors to apply this technology in different areas of science, including Biotechnology and Medicine. The CRISPR system was also used in food industries to modify probiotic cultures (e.g. in yogurts) to protect them from viral infection, in agricultural industries to improve the yield of crops, and in mammalian cells to study gene function. In 2017 it was also used as part of a research study to remove a defective gene from donated sperm, for an ethically approved scientific research study in human embryos, to treat an inherited genetic heart disease known as hypertrophic cardiomyopathy.

Although the CRISPR/Cas9 is a strong tool for genome-editing that will benefit many aspects of science as well as humankind, there are also a few limitations and ethical controversies regarding this technique. For example, some off-target effects were observed using this technology, like the recent study that attempted to repair a gene associated with hereditary blindness from the paternal sperm, in which unintended changes were reported in a big section of embryonic DNA. Although this technology aims to enable beneficial gene modifications in clinical practice, current studies highlight the fact that genome-editing research should be strictly regulated and ethically approved.

The discovery of this technique undoubtedly unfolds many favourable possibilities. However, such a powerful tool should be researched, understood, and utilized carefully and thoughtfully, if we are to succeed in harvesting it to benefit our everyday lives. It remains to the future to see the advancements of this new technology, and how the CRISPR/Cas9 tool, which gave the Nobel prize to Emmanuelle M. Charpentier and Jennifer A. Doudna, can rewrite the code of life.

A few words about the two scientists

Dr. Emmanuelle Marie Charpentier is a French professor born in 1968, whose work focuses on Microbiology, Genetics, and Biochemistry. Her research interests during her PhD focused on identifying molecular mechanisms involved in antibiotic resistance. Since then, Charpentier’s post-doctoral research was focused on mammalian gene manipulation, and she is now the director of the Max Plank Unit for the Science of Pathogens. Dr. Charpentier has been recognized with several honours and awards over the years, including the Canada Gairdner International Award in 2016, as well as the Kavli Prize in Nanoscience in 2018. She was also elected as a member of the Royal Swedish Academy of Sciences in 2015, and the European Academy of Sciences and Arts in 2018.

Dr. Jennifer Anne Doudna is an American biochemist born in 1964. She studied Chemistry in 1985 in California and then moved to Harvard University where she completed her PhD in Biochemistry. Her research focused on deducing the three-dimensional structure of RNA molecules in an attempt to understand their activity. Later in her career, she was interested in investigating the role of specific small RNAs and how they can regulate genetic information. Dr. Doudna also received many honors and awards such as the Gruber Prize in Genetics in 2015 and the Canada Gairdner International Award in 2016.

References used:

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