What is Genome Editing and CRISPR-Cas 9?
Everyone has genes which are made up of DNA, these define what makes us unique, or which part causes our sickness and disease. Obviously the ability to alter the part of our DNA which causes disease and sickness, would be a major breakthrough in biology and preserving human life itself. Therefore, over time scientists have eventually developed many different technologies attempting to edit, add and delete parts of our DNA, this is called Genome editing. Genome editing, involves exploiting an enzyme to edit a sequence of DNA, and once the DNA has repaired itself the change will now be in place. CRSPR-Cas 9 is the most current and simplest technique of editing one’s DNA sequence and involves an enzyme called Cas-9 which cuts the DNA, and in turn is replaced by the predesigned RNA.
Technical Overview of Genome Editing and CRISPR-Cas 9
The Genetics Home Reference from U.S. National Library of Medicine (2018) explain the CRISPR-Cas 9 technique of Genome Editing.
- Scientists design a piece of RNA which connects to a specific section of DNA within the gene, as well as an enzyme called Cas9.
- The pre-designed RNA is purposed with detecting the specific DNA section which is to be altered or removed. The Cas9 enzyme which the RNA is bound to, then makes the incision at the chosen location.
- After the section of DNA has been cut by the Cas9 enzyme, scientists adopt the cell’s own DNA repair techniques, to insert, remove, or alter the DNA by adding modified DNA sequences.
History of Genome Editing
In the beginning, around the early 1950’s, scientists began to theorise about genome editing after the discovery, that DNA is a double-helix structure. After analysis of the newly discovered double helix structure of DNA, scientists and researchers were able to identify that the base pairs, which make up DNA, are passed from parent to child, and small altercations between these pairs can lead to disease (Fridovich-Keil, 2017). The first true genome editing took place in the 1970’s and 1980’s and scientists harnessed the power of homologous recombination in an attempt to edit the genes of yeast and mice (Carroll, 2017). Over time researchers have used many different techniques, to accurately cut strands of DNA and edit genes, but it was not until 2012 when Jennifer Doudna and Emmanuelle Charpentier invented a way for manipulating CRISPR (Illman, 2017), the current simplest and most precise technique for genome editing.
Impact of CRISPR-Cas 9 Genome Editing
Manipulating CRISPR and Cas9 for the purpose of genome editing, has the potential to become one of the most disruptive technologies to date. It gives scientists the ability to edit the building blocks of our life, our DNA, and remove that sections that cause disease. The CRISPR genome editing technique has the ability to rid people of hereditary diseases and has currently had many successful cases with removing HIV from people.
According to Mark Crawford an author for the American Society of Mechanical Engineers (2017) there are 8 different ways that CRISPR-Cas9 will have a major disruption on the world:
- Researchers have been able to remove malaria from mosquitos by using the CRISPR-Cas9 technique to alter their DNA.
- Researchers are currently in the process of analysing DNA to find the cause of Alzheimer’s disease.
- Scientists have already been successful in removing DNA segments that cause HIV, using the CRISPR-Cas9 technique.
- Researchers will have the ability to develop new medicine to treat serious diseases, including blindness.
- Research scientists in China are currently working on using the CRISPR-Cas9 technique to modify the genes of livestock, so that we can more efficiently produce more wool, meat, milk etc.
- GMO’s. Biologists are using the CRISPR-Cas9 technique to genetically modify organics, such as crops. To increase such things as weather resistance and yield.
- Scientists have been researching into using the CRISP-Cas9 technique to modify immune system cells, to be able to attack and kill cancer cells.
- And Finally, researchers have figured out how to produce plastic from yeast by editing its genes with the CRISPR-Cas9 technique. Therefore, this will reduce the amount of CO2 omitted into the environment from large machines made to create plastics.
Cambridge Bioscience (2018). CRISPR/Cas9 Genome Engineering. [image] Available at: https://www.bioscience.co.uk/products/crisprcas9-genome-engineering# [Accessed 25 Apr. 2018].
Carroll, D. (2017). Focus: Genome Editing: Genome Editing: Past, Present, and Future. [online] PubMed Central (PMC). Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5733845/ [Accessed 25 Apr. 2018].
Crawford, M. (2017). 8 Ways CRISPR-Cas9 Can Change the World. [online] Asme.org. Available at: https://www.asme.org/engineering-topics/articles/bioengineering/8-ways-crisprcas9-can-change-world [Accessed 25 Apr. 2018].
Fridovich-Keil, J. (2017). Gene editing | genetics. [online] Encyclopedia Britannica. Available at: https://www.britannica.com/science/gene-editing [Accessed 25 Apr. 2018].
Illman, J. (2017). Timeline of scientific discovery: gene editing. [online] Raconteur. Available at: https://www.raconteur.net/healthcare/timeline-of-scientific-discovery-gene-editing [Accessed 25 Apr. 2018].
Reference, G. (2018). What are genome editing and CRISPR-Cas9?. [online] Genetics Home Reference. Available at: https://ghr.nlm.nih.gov/primer/genomicresearch/genomeediting [Accessed 24 Apr. 2018].
Yourgenome.org. (n.d.). What is genome editing? [online] Available at: https://www.yourgenome.org/facts/what-is-genome-editing [Accessed 23 Apr. 2018].