CRISPR-Cas9: A Possible Solution to Cancer
Written By: Arman Momeni
Cancer has been an illness that has long plagued humanity. The earliest cancerous growths in humans were found in Egyptian and Peruvian societies dating back to 1500 BC. Since then, the illness has only continued to grow. In 2022 alone, there were an estimated 1.9 million new cases of cancer and 609,360 cancer related deaths. After identifying that cancer was a gene-related illness in the late 1900s, scientists and researchers have been looking for outlets to suppress and possibly cure the condition.
Cancer:
Cancer, in general, refers to a wide variety of diseases that are caused by abnormalities in cell structure and function. Cancer cells divide uncontrollably and have the ability to destroy normal body tissue. Cancer cells also have the ability to spread through the body and attack different organ systems. Cancer symptoms vary based on which part of the body is affected, however, general symptoms include fatigue, pain, and a lump that can be felt under the skin.
Cancer is caused by mutations to the DNA (the carrier of genetic information in living organisms). DNA is normally packed tightly within the nucleus of a cell and contains a set of instruction (the genetic information), which directs cell function and behaviour. In cancerous cells, a mutation has affected these instructions and provides the cell with incorrect information on how it should function. These errors in the instructions cause the cell to behave in an abnormal manner and become “cancerous.”
A healthy cell detects and fixes mutations, divides at a healthy rate, works with other cells to perform a beneficial function, and destroys itself when it is no longer healthy. On the other hand, a cancerous cell goes rogue; it divides rapidly, does not stop dividing, provides no useful function to the body, steals nutrients from other cells, and spreads (metastasizes) to other parts of the body.
Cancer causing gene mutations can occur for two main reasons; either you are born with a genetic mutation that you inherited from your parents, or your genes mutate, for some other reason, after you are born. There are many factors that can cause a genetic mutation, such as radiation, viruses, smoking, carcinogens (cancer-causing chemicals), or lack of exercise.
CRISPR -Cas9
Now that scientists and researchers have established that cancer is the cause of mutations in the DNA, they have been looking for ways to correct the mutations through a method known as gene editing. While a revolutionary concept, gene editing has been deemed very inefficient and expensive. However, recent breakthroughs in the technology are shining a light on the possible outlet of gene editing. In 2012, CRISPR-Cas9 was discovered, which allowed humans to make precise and calculated changes to the DNA of living organisms in an efficient and effective manner. The precision and efficiency of the CRISPR-Cas9 model revolutionize the gene editing process and allow for increased accessibility to the technology.
The first part of the mechanism is CRISPR. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a defense system that was first found in bacteria, and forms the basis of the CRISPR-Cas9 system. CRISPRs where first discovered in unicellular organisms as an integral part of their immune system, which defend against invading viruses. CRISPR consists of repeating sequences of genetic code, and essentially act as a DNA storage system, which helps to detect and destroy possible threats when they return, as the bacteria recognizes that they do not match its genetic code sequences. Cas9, on the other hand, is a protein/enzyme, which acts as a pair of scissors to cut a specific DNA strand at a distinct location, so that it can be replaced and fixed. Another crucial component of CRISPR-Cas9, which is not in the name, is gRNA. gRNA, which is short for guide RNA is a molecule, which binds to Cas9 and provides Cas9 with directions on where to cut the DNA.
Works Cited
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