When it comes to the ever-changing landscape of genetics, the buzzword that appears to keep making its way to the fore seems to be the CRISPR. People have called it revolutionary, game changer, and even controversial, so what is CRISPR?? and why is everybody so excited about it?
This article is an introductory guide to the CRISPR technology, what it is, how it works, as well as the reasons why it became one of the most significant scientific discoveries in contemporary biology. Afterward, you will be familiar with the basis of this potent tool, after which you will be introduced to more advanced applications such as SHERLOCK and DETECTR.
What is CRISPR?
CRISPR (pronounced as crisper) is the acronym of Clustered Regularly Interspaced Short Palindromic Repeats. The name might seem very tricky; however, the too technical name belies a very simple explanation behind what a CRISPR is; it is nothing more than a bacteria-based defense mechanism. It is fundamentally a memory bank, which is genetic and assists bacteria to identify and to resist the viruses, that attack it.
Consider that bacteria are in a continual attack by a virus. Gradually, certain amongst these micro organisms have been activating a method of storing the genome of viruses that have afflicted them. These viral fragments are incorporated into the bacteria DNA in the sections called CRISPR. The bacteria store the information so that in case the virus comes back, they are able to eliminate it.
Then how did this bacterial self-defense mechanism turn into a human revolutional gene editing tool? That is where magic comes along
The Way CRISPR Imitates a Bacterial Immunity
I want to visualize how the CRISPR works in nature in order to understand how it works in gene editing.
- Recognition: In a case where a virus enters a bacterium; then the bacterium can cut one fragment of the Viral DNA and slips it into its own genome, at the site of CRISPR.
- Memory: These segments of DNA are nothing less than a memory machine, and these segments hold the memory of the virus so that the bacterium can be reminded of the virus.
- Defense The bacteria will already have the written sequences and reproduce them into RNA in case of the same virus attack. This RNA directs one of the Cas proteins (more downbeat later) to the complimentary viral DNA.
- Attack: Cas protein shreds up the viral DNA, successfully annihilating the infiltrator.
It was found in the 1980s but not until 2012 was the full potential to edit the genes in other organisms, which included both plants and animals as well as humans.
Abbreviation of Cas Proteins The Genetic Scissors
At the heart of the gene-editing capabilities of CRISPR is a battery of protein regulators known as Cas (standing for sale CRISPR-associated). Cas 9 is the most popular and widespread of them.
Cas9 acts as a pair of cutting scissors. However it does not work in solitude. It collaborates with a guide RNA the small strand of RNA which matches the sequence of the DNA that scientists wish to edit. Collectively, the guide RNA helps Cas9 to find its intended position in the DNA, and Cas9 cuts on a specific site at its appropriate location.
When the DNA is cut, then there is an attempt in the cell to mend the breakage automatically. In this healing process, scientists are able to:
- Turn off a gene (by allowing the cell to fix it wrongly),
- Fix a mutation (by supplying a correct template of DNA),
- Insert a new gene, altogether.
That is why CRISPR-Cas9 has become one of the revolutionary instruments of gene editing.
Find out more of CRISPR technology and gene editing at CRISPR Therapeutics
Why the CRISPR is Such a Big Deal
Prior to CRISPR alternatives existed but editing the genes was significantly more costly, less precise and much more complex. The game was transformed by CRISPR. The key strengths of it are:
- Accuracy: CRISPR can work at a very narrow part of the DNA.
- Efficiency: It is rapid and dynamic to a variety of cells.
- Accessibility: It is not very expensive and less laborious to operate as compared to their analogues of gene editing techniques of the past.
These properties have led to new avenues of interests in medicine, agriculture and biological studies.
CRISPR Usages in the Real World
Now, we should examine in more detail the positive use of CRISPR in the modern environment:
1. Medicine
Of the genetic diseases that CRISPR has a potential to cure include:
• Sickle cell anaemia
• Cystic fibrosis
• Muscular dystrophy
Crispr CRISPR has already been tested in clinical trials using it to cure these diseases by editing the incorrect genes that cause the disease involved.
2. Cancer Therapy
Researchers are experimenting to have immune cells edited using CRISPR in order to enable the immune system recognize more cancer cells and destroy them. During certain trials, cells edited with CRISPR are being used on leukemia or lymphoma patients as a course of treatment.
3. Infectious Disease
Fast and accurate detection of viruses such as SARS-CoV-2 under low-resource conditions is also possible with the help of CRISPR-based tests, such as SHERLOCK and DETECTR (which will be discussed in the following articles).
4. Agriculture
CRISPR is assisting in producing crops that are nutritive and that do not need a lot of chemicals to control the attacks of insects and other pests.
So is CRISPR safe?
As all strong technology, CRISPR brings ethical and security concerns to mind.
- Off-target effects: It also occurs that CRISPR cuts DNA into places it is not supposed to causing unplanned changes.
- Germline editing: Also known as embryo or germ cell editing (embryos and reproductive cells are capable of passing modifications to future generations), germline editing is highly disputed and is strictly regulated in most of the countries.
- Access and equity: Who can have ownership to CRISPR? Will it come at an affordable price to everyone or at a selective few?
Scientists are trying their best to improve the technology, minimize the risk and establish ethical standards of its application.
CRISPR vs. Other Genetic-Manipulating Technologies
Prior to use of CRISPR, there are other techniques that were employed by scientists including:
Zinc finger nucleases (zfns)
TALENs (Transcription Activator- like Effector Nucleases )
These methods are complex, expensive yet effective although they are not very customizable. The ease and versatility of CRISPR have rendered it the tool of desire in research facilities across the globe.
Whether CRISPR is Revolutionizing how we do science
It is a fact that CRISPR is changing the face of scientific research more than being a mere tool of DNA editing. Here’s how:
- Quicker research: The research process has been inordinately quicker with scientists being able to develop animal models of disease a whole lot faster.
- Functional genomics: CRISPR assists in determining what genes do, by switching them off and seeing what differences occur.
- Gene drives: Scientists want to use CRISPR to fix genetic properties into the population of insects, such as in the case of diseases like malaria.
CRISPR is also under scientific research to understand how the brain works, aging, stem cells, even resurrect extinct species in small scale research.
The Most Popular Myths About CRISPR
And it is easy to get swept by the hoo-ha, so some clarifications are as follows:
- CRISPR is not a tool of new designer babies (yet). Although theoretically this form of germline editing is possible it is prohibited in most jurisdictions.
- It is not entirely true. Investigators continue to develop the accuracy of targeting.
- It does not work like magic. CRISPR is not a cure-all it is a tool. It is prone to succeed on the basis of numerous intricate biological considerations.
- Knowing the capabilities and limitations of CRISPR can help weigh up realistic expectations of it in the future.
Tomorrow of CRISPR
In the future, it is possible that CRISPR will transform whole industries. One of them is:
- Personalized medicine: Made to the individuals own genetic code.
- Elimination of genetic disorders: Correcting the aberrations in the genes permanently before the aberrations lead to the disease.
- Climate-proof crops: Making foods secure in the era of global warming.
- Biosensors and diagnostic: Fast on-the-field or home disease detection.
Future improvements such as base editing (which is seen as a more specific version of CRISPR) and prime editing (whereupon DNA can be re-written with fewer incisions) could neutralize existing restrictions and enhance the capabilities of the tool even further.
Conclusion: The Reason Behind the Importance of CRISPR
The move to the spotlight of scientific innovation has turned a mysterious bacterial oddity into CRISPR. It is one of the most useful tools in the modern biology because of its capacity to edit genes with a level of precision and ease that was not achieved before.
As first of all, the idea of CRISPR as an imitation of a bacterial immune system, Cas proteins as genetic scissors and the guide RNA as the one who drives the system towards a definite DNA sequence can be of great use as emergent in this case. Be it curing disease or enhancing crops, or making scientific discovery, CRISPR technology is the dawn of a new period of human potential.
The science has not entered a final shape, yet the one thing is evident, CRISPR is here to stay, and its effects on the world are just starting to be shown.
What is next: Let us explore further the CRISPR-based diagnostics with our article about SHERLOCK and DETECTR.
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