#SCIENCE | CRISPR-Cas9: Change for the Better, One Gene at a Time

by Alano Ines and Cyril Lati

An illustration of how Cas9 edits genes. Picture taken from researchgate.net

What is CRISPR-Cas9?

CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a group of DNA sequences that are derived from DNA fragments from bacteriophages that have infected a prokaryote. These sequences are then tasked to search and destroy any similar bacteriophages that try to infect that organism. Meanwhile, Cas9, which stands for CRISPR-associated protein 9, is a protein that is able to cut DNA, which gives bacteria with Cas9 the ability to alter any genome using this protein. The discovery of CRISPR-Cas9 was actually by accident. A group of scientists were conducting research on bacteria, specifically E.coli. At first, the scientists didn’t know what the function of Cas9 was, but their discovery sparked a multitude of scientists to conduct research on these sequences, and their work has led to the current status of CRISPR-Cas9 technology today.

In the past decade, scientists have been able to experiment with Cas9 and essentially use it as a genome editing mechanism, one that is applicable to any organism and is fast, cheap, and easy to use. A laboratory procedure that used to take months is now possible in mere days, or even hours. The use of Cas9 allows for a variety of things to be done to genes, such as removing harmful genes or transplanting useful genes. This makes way for a variety of practical applications in a multitude of industries.

Where can Cas9 be used?

Cas9 can be used in a wide variety of industries, such as agriculture, textiles, healthcare, and research. With regards to research, Cas9 is able to help geneticists find out the uses and functions of the vast amount of human genes that have yet to be analyzed. This can be done by observing what happens in the presence and absence of a specific gene, which can be hard when the gene is surrounded by other genes that may or may not have an effect on the observed gene. This is precisely why Cas9 helps scientists analyze specific genes, because it allows for the isolation of these genes, allowing for the removal of external factors that can change the response of a cell.

Meanwhile, Cas9 has the potential to revolutionize the agricultural industry. With regards to crops, Cas9 can be used in a multitude of ways, such as improving the immunity or resistance of crops to pests, disease, and unfavorable environments. Cas9 can also be used in increasing the yield of crops, allowing for more efficient farming, and increasing the food supply to fit the growing demand of a similarly growing population. Cas9 also allows for crops to be grown in areas where they normally cannot, due to environmental conditions like temperature, humidity, water supply, and many more. With regards to livestock, Cas9 can be used in increasing the yield that can be gained from animals, such as increasing the wool that can be sheared from sheep, or the meat you can eat from animals like cows, chickens, and pigs. It can also increase the resistance of livestock to diseases, environmental harms, and other risk factors. For example, pigs can develop immunity against diseases like African Swine Fever by having their genomes edited to include genes responsible for producing antibodies familiar with the virus.

With regards to healthcare and medical research, Cas9 can be used in two ways.The first possible approach is hampering or mitigating disease-carrying organisms like mosquitoes, and other vectors by increasing their immune response against pathogens, thus killing these pathogens before they can be transmitted to humans. The second possible approach is directly improving the resistance of humans against pathogens by increasing the effectiveness of the immune system. However, this approach may come with a few ethical concerns regarding human experimentation and tampering with a human subject’s genetic makeup. Even with all these concerns, it is still a valid approach with regards to the ability of doing these processes on a human.

How can Cas9 be applied in a Philippine context?

There are many problems that have plagued the Philippines with regards to its industry and healthcare throughout the decades. Problems regarding the security of crops and livestock, malnutrition, and a multitude of pathogen-borne diseases are among the issues that can be alleviated through the usage of Cas9 technology.

In the agricultural sector, common crops can be made more resistant to disease, pests, and other environmental factors. Apart from this, their yield and quality could also be improved to adapt for the daily needs of the country’s citizens. Rice, a staple in Filipino households everywhere, are in constant risk of crop failure due to drought, pests, and diseases prevalent in our country. By using Cas9, this crop’s resistance, yield, and quality could all be improved upon. This effect would last for generations, improving the standard of agriculture in the country in the future.

In the healthcare sector, disease carriers such as mosquitoes can have their immune systems edited so that they will be more sensitive and responsive towards diseases such as malaria and dengue. By releasing gene edited mosquitoes into the wild, the mosquito population can soon be resistant to these diseases, and be able to mitigate the transmission of these to the populations. Cas9 can also be used to improve the quality of food consumed by the population. This can be done through the aforementioned increase in yield, or by improving the quality of food produced through enhancing its capabilities with regards to making beneficial nutrients and the like.


As scholars of the nation, utilizing and improving revolutionary technology such as Cas9 should be a primary goal. With all of the possible ways that this form of technology can help our country, it is but a matter of time before change for the better can happen, one gene at a time.




The official English-language publication of the Philippine Science High School–Main Campus.

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