How Women Revolutionized Modern Science

Jennifer+Doudna%E2%80%99s+CRISPR+discovery.

Photo from U.S. GAO.

Jennifer Doudna’s CRISPR discovery.

In light of this past Women’s History Month, it is important to recognize women in one of the most male-dominated fields across the globe: STEM. Women make up about 28% of the STEM workforce, and wage gaps in high-level fields like computer science and engineering are prominent. However, these prevalent shortcomings did not stop Jennifer Doudna from becoming drawn to the science field from a young age. This interest earned her a Ph.D at Harvard in 1989 and allowed her to work among the best biologists in the world, such as Jack Szostak, who later won the 2009 Nobel Prize in Medicine. However, the success did not stop there: as her keen interest in biology would later lead to one of the most revolutionary and life-changing discoveries of our time.

In 2005, Doudna shifted her attention from RNA to unusual DNA sequences found in bacteria – specifically, repeating sequences of viral strains with unique spacer sequences in between. These clusters are called CRISPR, for “Clustered Regularly Interspaced Short Palindromic Repeats.” Viral strands that have entered the DNA are cut by an enzyme called Cas9 and stored within the sequence located inside the protein. This way, CRISPR acts as a search device, and Cas9 cuts the selected DNA strand. Using this logic, Doudna realized that CRISPR “base editors” can edit genetic material by cutting the selected strand and replacing it with artificial genetic information made in a lab.

The process begins with Guide RNA (gRNA). RNA carries genetic information from DNA to ribosomes to initiate protein synthesis. Guide RNA will find the part in the cell nucleus (where most genetic material is stored) where gene editing takes place. The gRNA instructs the spot for the Cas9 protein to cut, breaking open the double-stranded DNA. When DNA is broken, cells are instructed to repair the break. Cells typically fix DNA by gluing loose ends back together, which can be useful in the gene editing process. Repairing a break can disable a gene, fix a mistake, or insert a new gene. In the case of CRISPR/CAS9 technology, lab created DNA will be inserted to replace a gene.

This process can be lifesaving to many suffering with genetic disorders. Scientists can compare mutated/non-mutated cells to pinpoint where mutations occur. The CRISPR/CAS9 team can use this to disable certain genes that play a role in genetic/inherited diseases such as cancer and sickle cell anemia. The tools can cut a single nucleotide base or add a certain protein. Also, the human germ line can be engineered to prevent future generations of inheritance to deadly diseases. Families of patients with inherited diseases have shown great support for this technology, especially with its growing efficiency of 50-80% in clinical trials.

Overall, these tools can play a huge part in saving lives. This earned Doudna and her colleague Emmanuelle Charpentier the 2020 Nobel Prize in Chemistry. This was not only a win for the scientific community, but a win for women in STEM and all aspiring female scientists. 

“I think that for a lot of women, there’s a subtle but unfortunately effective discouragement of women pursuing the STEM fields Women have natural curiosities, as do men, and we just want to show women they can pursue these fields and they can be feminine, they can be mothers, they can be wives—they really can do all those things and do it on their own terms.” – Jennifer Doudna