Genome editing includes various technologies that allow scientists to alter the DNA of an organism. One example of genome editing (also referred to as gene editing) is CRISPR Cas9, which is creating significant waves in the science world. It has shown significant progress in disease eradication and food security. The CRISPR Cas9 editing sequence allows scientists to use human bacteria cells to remove portions of the DNA of a virus, keeping those portions to promote a stronger immune response. The sequence can also potentially boost plant and crop quality and yields, help plants become more resistant to droughts, and improve product shelf life.
Understanding the CRISPR Cas9 editing process can be helpful for understanding the impact of their various applications, and any new uses it make have the future.
What Is CRISPR Cas9 Gene-Editing?
CRISPR Cas9 stands for Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and the associated protein number nine. Scientists are excited about this system for gene editing because it has proven to be more accurate, more efficient, faster, and less expensive than other genome editing methods. Scientists adapted the system from a genome system that occurs naturally in bacteria.
The bacteria use snippets of DNA from viruses that invade, capturing them and using the DNA snippets to create segments of DNA known as CRISPR arrays. These arrays allow the bacteria to recall the virus that invaded, as well as any closely related viruses. When those viruses attack once again, the bacteria can produce related RNA segments from the created CRISPR arrays, which target the DNA of the viruses. The final step in the process involves the use of Cas9 or a related enzyme to tear the DNA apart, effectively disabling the virus and preventing it from reproducing and spreading.
CRISPR Cas9 Gene Editing Process
In order to work, the genome editing system requires two key molecules that can introduce a change to the DNA. The first is the enzyme, which is known as Cas9. It can split the two DNA strands at a designated location in the genome, allowing for the addition or removal of DNA bits at that location.
The second molecule is a section of guide RNA (gRNA). The gRNA includes about 20 bases, which make up the pre-designed RNA sequence within a longer scaffold of RNA. This binds to the DNA, guiding the Cas9 to the proper location within the genome to split the strands. When this occurs, the cell recognizes that damage has occurred and attempts to repair the DNA.
Applications of CRISPR Cas9 Gene-Editing
Using the naturally occurring process has allowed scientists to effectively recreate the CRISPR Cas9 gene editing process and use it in a number of applications. In the medical world, scientists are looking into this method to treat medical conditions that include genetic components, such as high cholesterol, certain forms of cancer, and hepatitis B. The process has also generated interest as to whether it could work to edit reproductive cells.
Further understanding CRISPR Cas9 gene editing and its applications, as well as its potential, can be beneficial, particularly for those in the biofuel, healthcare, and agricultural industries. Learn more about this hot topic in a course focused on the potential of the genome editing system offered by Harvard University.