Rewriting the Code of Life: The Blessings and Burdens of Gene Editing
Imagine having a magic wand that could rewrite the story of life, fixing genetic typos and making the impossible, possible. Imagine being able to cure diseases and solve world hunger just with a swish of your wants. Though we don’t have real magic wands yet, gene editing is the closest thing we have to it. Gene gives us the ability to become superheroes of science, fighting off diseases and painting a brighter future for the next generations. But with great power comes great responsibility. Gene editing is a powerful tool and can be used to solve many problems. However, if used the wrong way it can lead to serious consequences. Get ready to dive into a world where science meets science fiction, where genes become the characters in a saga of innovation and ethics. Welcome to the captivating realm of gene editing.
DNA
Before going any further, we need to understand the basics of gene editing. DNA, which stands for deoxyribonucleic acid. DNA is a molecule that is found in all living organisms. It’s known as the genetic blueprint for all organisms, as it contains the “instructions” for building, maintaining, and operating an organism.
DNA has a double-helix structure, meaning there are two DNA strands twisted around each other. DNA has three main components: the phosphate group, pentose sugar, and nitrogenous base. The nitrogenous bases are what make up the information in DNA. There are four types of bases: adenine (A), thymine (T), guanine (G), and cytosine (C). Each of these pairs is arranged in a specific order and paired together (adenine pairs with thymine and guanine pairs with cytosine), coding specific instructions to maintain and build organisms. Think of DNA as a ladder; the phosphate group and pentose sugar are the sides of the ladder, and the nitrogenous bases are the steps on the ladder.
How does Gene editing work?
Now that we understand what DNA is, we can move on to how gene editing works. In simple words, gene editing is like cutting paper with scissors. The paper is the DNA in need of editing, and the scissors are the gene-editing tool for completing the edits. Let’s take a look at CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats), a gene editing tool that allows scientists to make precise cuts in the DNA. CRISPR-Cas9 has two main components: a guide RNA and the Cas9 protein. The guide RNA is used to help find the gene that you want to edit and guide the Cas9 protein to that location. Cas9 protein is a special protein that cuts the DNA so that changes can be made. The Cas9 has two parts, one for cutting the DNA and the other for recognizing the code. To understand how CRISPR-Cas9 works, let’s imagine ourselves as book editors.
- Target Identification - Identifying the error: You’ve been given a manuscript to review. Your job is to identify and correct errors in the text, such as typos, grammar mistakes, or factual inaccuracies. In CRISPR, the first is like identifying errors in a book. Scientists will identify the sequence of DNA they would like to edit; the DNA sequence is like the paragraph that needs corrections.
- Designing RNA - Creating the blueprint: We now need to decide how to fix the errors. You might create a list of corrections and notes on what and where to change things in the book. Similarly, the guide RNA is designed to match the target DNA sequence, providing the “instructions” for the editing process.
- Cas9 -Editors Toolkit: As an editor, you need tools to complete your edits. You may use a red pen or a word processor. For CRISPR, the Cas9 protein is the editor. It is a molecular scissors that cuts the DNA.
- Making the Edits - Cutting the DNA: You now make the changes in your book based on your notes. The Cas9 protein, guided by the RNA blueprint, is used to cut the DNA at the specific spot. This is equivalent to making the actual changes in the book’s text.
- DNA Repair - Inserting Corrections: After the DNA is cut, the DNA natural repair system is triggered. This is to fix the cut DNA. It’s like a book getting fixed by the author or proofreader.
6. Verification and final proofreading: After the correction, a final proofreading must be done in order to make the corrections correct. When it comes to CRISPR, scientists will verify that the corrections were correct before growing the cell.
The blessings of gene editing
Gene editing is like the superhero of modern science. It’s got a whole bunch of pros that can’t help but make you excited. First off, it’s a game-changer in the world of medicine. Genetic diseases can be cured with gene editing, saving millions of lives that have been haunting us for ages. It is also a game changer in agriculture, helping food become more resilient to the ever-responsive climate. Let’s dive deeper into what gene editing offers us.
Disease-Free Utopia
Conditions like cystic fibrosis have affected millions of lives. Did you know approximately 70,000 people are diagnosed with it worldwide? What’s the reason we have these genetic mutations? The answer lies within our DNA. A mutation is when there are changes in a DNA sequence. Remember how DNA is made up of four nitrogenous bases (A,T,C, and G) and that they will pair with only one other base pair? If one of these pairs is not paired up correctly or the sequence pairs are messed up in one part of the DNA, a mutation occurs. Mutations can also occur when there is an error in cell division (the process in which one cell, called the parent cell, divides to form two new cells, referred to as daughter cells).
When it comes to curing these diseases, there are various factors that scientists have to keep in mind.
- The type of disease Not one genetic disease is the same. Some are relatively single-celled-gene diseases (cystic fibrosis) or complex diseases (heart disease). Depending on the type and complexity of the disease, it depends on how easy it is to find a cure for it.
- Individual variables. Genetic diseases can affect individuals differently. Scientists have to make sure that the cure is personalized to the individual’s unique genetic makeup. This is called personalized medicine.
What companies are taking action to help cure these genetic diseases?
Spark Therapeutics is a company dedicated to furthering advancements in healthcare through the application of gene therapy. They have established an integrated gene therapy platform with the goal of converting genes into therapeutic solutions for individuals with genetic disorders. They are working on diseases like:
- Inherited retinal diseases (IRDs)
- Hemophilia, a liver-directed disease
- Pompe and Fabry, lysosomal storage disorders
- Neurodegenerative diseases.
BioMarin Pharmaceutical specializes in treatments for rare genetic diseases like phenylketonuria (PKU) and mucopolysaccharidosis (MPS). The specializes particularly in the areas of enzyme replacement and gene therapy. Their mission is to provide life-changing therapies for patients with unmet medical needs caused by rare genetic diseases.
Customized Crops
Have you ever read the sign on any produce bag saying “non-GMO product”? It’s a clear indicator of the ongoing conversation about gene editing in agriculture. GMO stands for Genetically Modified Organisms. What is does this mean? It simply means that an organisms gene’s are edited to change or add a trait to it. Why would you change the organisms genes? There are many reasons why you would want to do this.
- Improve crop yield: Many farmers use pesticides to get rid of any insects feeding on their crops. However the pesticides have harmful side effects on the environment. It can contaminate soils, water, and turf. Pesticides can also kill wildlife. Scientists used gene editing to reduce the amount of pesticides used by editing crops genes so that they can produce its own pesticide and not harm any wildlife.
- Resistance: With climate change making it hard for crops to grow, there is a need to make it easier to grow the crops. Gene editing can make the crops more resistance to the heat, reduce their need for water, and help with withstand any harsh climate.
How do GMOs work?
To understand how GMOs works lets look at how a corn is genetically modified.
- Identify Desired Trait: The first step is to identify the desired trait or characteristic you want to modify in the corn. Let’s say we want it to produce its own pesticide.
- Select Donor and Host Organisms: Now we have to choose a donar organism. The donor organism must have the pesticide trait we want. In this case the donor is Bt Bacterium which is a bacteria that is toxic to certain insect larvae. Our host organism is corn.
- Isolate the Gene: The next step is to isolate the gene that is in charge of producing the toxins. Molecular biology techniques are used to do this.
- Insert the Gene: Now that we isolated the gene in Bt Bacterium, we will now insert it into the corn. Plasmid (a small, circular piece of DNA), a bacterial vector, or direct gene insertion are used to do this.
- Promoter Sequence: To ensure that the newly inserted gene is active and produces the pesticide in the corn, a promoter sequence is added. This acts like an “on” switch for the gene.
- Transform the Host: The modified DNA is now introduced to the rest of the corns cells. Bacteria and virus are used to help complete this process.
- Selection and Cultivation: Not all the of the corn cells will successfully take up the modified DNA. The next step involves selecting the cells that have incorporated the desired genes and cultivating them to grow into complete organisms.
The Risks
Gene editing is a powerful tool. It can help save lives and change the way we eat. However, if used the wrong way it can lead to disastrous outcomes. An example of this is gene babies. In theory, these babies are genetically modified before birth. Though this is just in theory there have been some attempts to make this a reality, however has not succeeded to persuade the science community that this is a good idea. Many people were not found of the idea of changing a babies traits based on what the parents want their child to have.
Gene editing also raises questions like how can we ensure the safety of gene editing techniques in humans and other organisms? Should gene editing be used for human enhancement, and if so, where do we draw the line between therapy and enhancement? As humans, we have to draw a line between what will help humanity grow and our greed.
Blessing or Burden?
On one hand, gene editing is a blessing with the power to cure genetic diseases that have plagued humanity for ages. It holds the promise of changing the way we grow our food, making it more sustainable and potentially solving some of our world’s hunger problems. But on the flip side, it’s a burden because it comes with ethical dilemmas and concerns about tinkering with the very essence of life. Were talking about genetic code, the code of life. Something which should never be taken lightly. As a wise person once said “With great power, comes great responsibility”
Hi! My name is Tanvi and I’m a high school student interested in gene editing and emerging technologies in the medical field. If you have any questions, feedback, or simply want to connect, feel free to reach out to me on LinkedIn. Thank you for your time, and I hope you found something valuable in my work!
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