BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Gene-editing (Page 1 of 3)

New Approach to Gene Editing

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On April 11, 2025

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Recently, we learned about gene mutations during DNA replication. Firstly, we broadly covered what a gene mutation is: a change in the DNA sequence of a gene. Moreover, we gained an understanding of the various kinds of mutations. One of which was substitution: One nitrogenous base is replaced by another.

This kind of mutation can have disastrous effects. Take alpha-1 antitrustypsin deficiency (AATD) for instance. This condition is caused by a substitution mutation and can lead to emphysema or chronic obstructive pulmonary disease in unprotected lungs.

Recently, a cure may have been found in the form of a new approach to gene therapy. Typically gene therapy involves added new genes with the intention of counteracting present ones or splicing DNA to spliced genes. This new method involves altering current DNA. The therapy will change an incorrect nitrogenous base for the correct one.

Specifically, the procedure entails infusing lipid nanoparticles into the bloodstream via an inoculation of some kind. Encased within the nanoparticles are microscopic gene editors. These editors are CRISPR molecules that function as a guide for the genome and enzymes to fix the mutation. After the lipid casing of the nanoparticles has been peeled off, the gene editors will begin the process of replacing DNA bases.

These findings are extraordinary. Perhaps they will also mark the beginning of a something great. As Dr. Kiran Musunuru, of the University of Pennsylvania has stated, “this is the beginning of a new era of medicine.” With this sentiment I leave you the question of should the American government allocate more funding to CRISPR gene editing research?

Simultaneous Tracking: CRISPR’s Major Upgrade

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On April 7, 2025

In Student Post

Software updates on your iPhone can often feel unnecessary. Waiting for your smartphone to complete an increasingly lengthy update, only to discover seemingly minimal changes in one area—like fixing bugs or improving compatibility—can be frustrating.

People using smartphones at a railway station

Smartphone users at a railway station.

For the past decade, scientists have been able to edit DNA with remarkable precision, revolutionizing genetic research with the use of CRISPR-Cas9 technology. Specifically, CRISPR-Cas9 technology is a type of gene editing technology that allows scientists to use enzymes to molecularly cut and/or modify specific portions of DNA or RNA to discover the roles these genes play in a variety of disorders and diseases. According to the National Library of Medicine, CRISPR-Cas9 “makes it possible to correct errors in the genome and turn on or off genes in cells and organisms quickly, cheaply, and with relative ease.”

This is what makes CRISPR technology so amazing! The technology’s ability to, according to the Broad Institute, “easily be matched with tailor-made “guide” RNA (gRNA) sequences designed to lead them to their DNA targets,” makes the technology distinctly efficient and customizable in a way other gene-editing tools are not.

Although this type of genetic technology has led to significant discoveries regarding the roles of genes in cancers and autoimmune disorders, CRISPR has had a key limitation: it could only target one gene at a time. However, in a recent study, researchers at Yale University discovered a new upgrade in CRISPR technology that allows for simultaneous genetic modifications and tracking across multiple genes at once, a notable change from past CRISPR abilities.

CRISPR-Cas9 Editing of the Genome

Illustration of CRISPR-Cas9 Editing of a Section of DNA.

The research team’s new tool, called CRISPR-Cas12a, has the ability for researchers to “simultaneously assess the impact of multiple genetic changes involved in a variety of immune system responses.” Led by Dr. Sidi Chen, the team of researchers developed four mouse models that used this new technology to fine-tune and track changes in the mice’s immune system cells. The team distinctly focused on inducing and editing sets of genes in “different directions simultaneously.”

These models essentially allowed the scientists to study the genetic interactions of the mice’s immune system cells that contributed to diseases like cancer and even autoimmune and neurological disorders. In this way, Chen’s team was able to create an entirely new way of studying immune responses at the genetic level not only for mice cells but for human cells as well, which could eventually develop into the creation of new remedies and therapies for certain types of medical conditions and diseases.

This research directly connects to what we’ve studied recently in AP Biology. CRISPR-Cas12a and other gene editing technologies relate directly to the ability to manipulate transcription and translation during protein synthesis through gene regulation. Moreover, we learned in class that genes control traits by coding for different types of proteins and that cells can turn their genes “on” or “off” through a series of regulatory processes. CRISPR-Cas12a connects to our classwork because this technology allows scientists to modify multiple genes at once and observe how those changes can affect how certain cells function and what phenotypes are shown as a result. By editing multiple genes, scientists can study how genes work together to create traits!

Cas12a (Cpf1) in complex with crRNA and target DNA

Structure of CRISPR-Cas12a with a guiding RNA (cRNA) and target segment of DNA.

Ultimately, CRISPR-Cas12a and other types of genetic technology have great implications for the future of medicine and genetic testing. The ability to edit multiple genes simultaneously has created promising hopes for the development of new, personalized medicinal treatments and the improvement of scientists’ understanding of genetic diseases and immune system disorders.

It is clear that the future of medicine is continuing to be crafted, one gene at a time—or in this case, many at once!

Mice and Mutations- A new gene editing tool in the fight against Alzheimer’s

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On April 7, 2025

In Student Post

Certain genetic mutations have the ability to alter a protein’s whole amino acid sequence and warp proteins into toxic, misfolded shapes which disrupt cellular functions. These mutations can eventually lead to diseases such muscular dystrophy, Huntington’s disease, and Alzheimer’s. 

In most areas, genome editing technology has become a critical tool in targeting toxic proteins and fighting against diseases such as cancer, HIV, and sickle cell anemia. CRISPR technology (clustered regularly interspaced short palindromic repeats) is frequently utilized, employing a Cas9 protein and guide RNA to target specific and edit specific DNA sequences. 

Neurodegenerative diseases including Alzheimer’s and Parkinson’s are strongly associated with accumulation of misfolded proteins in the brain. This specific protein misfolding is influenced by a variety of factors and is seen as very complex. While CRISPR/Cas9 has potential for correcting the protein misfolding associated with neurodegenerative disorders, another new gene editing tool SPLICER, is coming in hot to address this problem. 

To test the capability of SPLICER’s promise in gene editing for neurodegenerative disorders, a research team from the University of Illinois conducted a study to test if SPLICER can reduce plaque accumulation in the brains of live mice, potentially lowering the risk of Alzheimer’s disease. 

SPLICER is a gene-editing tool that utilizes exon skipping, a technique that modifies gene expression by skipping and splicing certain exons during the protein synthesis process. Built upon the CRISPR gene editing platform, SPLICER offers greater flexibility. Traditional CRISPR-Cas 9 gene editing systems require a specific DNA sequence to latch on, bind, and edit genes, limiting which genes can be edited. However, SPLICER employs newer Cas-9 enzymes that function without these restrictions. Additionally, there are two important sequence areas, one at the beginning and end of a gene, that make cellular machinery aware of which parts of a gene to use for protein synthesis. While CRISPR and traditional exon skipping tools use only one of these sequences, SPLICER edits both, allowing the exon-skipping process to be more efficient. 

Alzheimers disease beta-amyloid plaque formation-2

The Illinois team targeted a specific exon in an Alzheimer’s related gene that codes for an amino acid sequence within a precursor protein. Usually, this protein would undergo a modification where it gets cleaved to form amyloid-beta, a peptide which accumulates to form plaques on neurons in the brain. While analyzing the DNA and RNA output in SPLICER treated mice, it was discovered that there was a significant decrease in amyloid-beta production. The researchers found that the targeted exon was reduced by 25% in the SPLICER-treated mice, demonstrating the effectiveness of this technique. 

As a part of our recent Molecular Genetics Unit, we have learned the process of gene expression, where a portion of DNA is transcribed into an mRNA strand, which is then translated into a peptide chain and forms a protein. However, after the transcription of the mRNA, RNA splicing occurs where a spliceosome cuts out the introns (non-coding sequences) and joins the ends of exons (the coding/expressed sequences) together. The purpose of SPLICER is to remove specific exons or coding sequences from the mRNA, potentially producing a modified but still functional protein after the translation phase and reducing the formation of misfolded and toxic proteins. 

The study concluded that SPLICER, which combines newer base editors with the dual sequence editing, enabled exon skipping at a much higher rate than older available technologies. By efficiently skipping target exons in the mice, the tool reduces amyloid-beta production, leading to less plaque buildup and a lower likelihood of developing Alzheimer’s or other neurodegenerative diseases. 

However, this approach does have limitations. Exon skipping only works if the product protein is still functional, meaning not all diseases can be treated this way. However, for diseases like Alzheimer’s, Parkinson’s, Huntington’s or Duchenne’s muscular dystrophy, this approach holds a lot of potential. Further research is needed to confirm that removing targeted exons is safe and does not lead to the production of toxic and nonfunctional proteins. While SPLICER represents a significant advancement in gene editing, continued research and refinement are necessary before it can be considered for human application. 

As part of my Independent Service Project, I will be volunteering with adults who are suffering from dementia and other neurodegenerative diseases. Even before beginning this work, witnessing and understanding the challenges they face each day has strengthened my hope for advancements in treatment. While continued research and refinement are necessary before SPLICER technology is considered for human application, I am grateful that we are making progress to combat these devastating diseases. 

https://www.sciencedaily.com/releases/2024/12/241223153410.htm– original article

https://www.xiahepublishing.com/m/1555-3884/GE-2024-00002–  additional research on CRISPR technology

How CRISPR is Changing the Way We Treat Illness

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On April 7, 2025

In Student Post

Introduction: Imagine a world where genetic diseases like sickle cell disease (SCD) are no longer a life sentence. Recent advancements in gene editing, particularly using CRISPR technology, are turning this vision into reality. As an AP Biology student fascinated by genetics, I was captivated by a groundbreaking therapy that utilizes CRISPR to treat SCD, a condition we’ve explored in our studies on genetic mutations and their physiological impacts.

 

Summary of Main Research Article:

 

A recent article titled “Cutting Edge Gene Therapy” discusses the development and approval of Cassava, a CRISPR-based gene therapy for individuals suffering from sickle cell disease (SCD) and transfusion-dependent beta-thalassemia (TDT). Researchers discovered that higher levels of fetal hemoglobin (HbF), which has a higher oxygen affinity than adult hemoglobin, can alleviate symptoms of these diseases. Casgevy works by editing blood-forming stem cells to promote HbF production, thereby reducing the impact of SCD and TDT. Clinical trials indicated that 93.5% of SCD patients did not experience pain crises for at least a year post-infusion. Notably, this therapy became the first CRISPR-based treatment to obtain FDA approval in December 2023. 

Orginal Article: https://time.com/7094725/vertex-pharmaceuticals-and-crispr-therapeutics-casgevy/

Additional Resources:

 

  1. Innovative Genomics Institute: CRISPR Clinical Trials Update https://innovativegenomics.org/news/crispr-clinical-trials-2024/

 Provides an overview of ongoing CRISPR clinical trials and their implications.

 

  1. Nature: CRISPR genome-editing grows up https://www.nature.com/articles/d41586-024-04102-w

 Discusses the maturation of gene-editing technologies for treating various disorders.

 

Connection to AP Biology:

 

In our AP Biology curriculum, we’ve studied the central dogma of molecular biology, which describes the flow of genetic information from DNA to RNA to protein. Sickle cell disease is caused by a point mutation in the β-globin gene, leading to the production of abnormal hemoglobin S. This mutation results in red blood cells adopting a sickle shape, causing blockages in blood vessels and leading to pain and organ damage. The CRISPR-based therapy directly relates to our discussions on gene expression and mutation impacts, as it involves editing the genome to reactivate the production of fetal hemoglobin (HbF), which can compensate for the defective adult hemoglobin. This therapeutic approach exemplifies the practical applications of our understanding of gene regulation and expression.

 

Personal Reflection:

 

The potential of CRISPR to cure genetic diseases is both exciting and thought-provoking. Learning about Chevys success in treating SCD patients without pain crises for extended periods is inspiring. However, it also raises questions about accessibility and long-term effects. How can we ensure that such groundbreaking treatments are available to all who need them? What ethical considerations should guide the application of gene editing in humans? I’d love to hear your thoughts on these issues.

 

Tags: CRISPR, gene editing, sickle cell disease, gene therapy, fetal hemoglobin

 

Images:

< Diagram explaining steps behind simple CRISPR-based diagnostics

 

This figure shows how CRISPR can be used for quick diagnostics in addition to gene editing. Scientists can develop extremely sensitive, field-deployable diagnostic assays by employing CRISPR proteins to identify particular viral or bacterial DNA sequences. Even though I wrote a piece about gene therapy, this demonstrates how CRISPR technology has many uses outside of medicine and is changing the way we identify illness.

 

 

 

CAS 4qyz

 

The Cas9 protein, the molecular “scissors” in CRISPR systems, is depicted in this 3D model. Cas9 finds and cuts specific DNA sequences under the guidance of RNA, allowing for accurate modifications. The physical complexity of this protein reminds me that even the tools we use to rewrite DNA are themselves the result of evolution — making CRISPR a case of biology editing biology.

 

CRISPR-Cas9

 

This picture explains the CRISPR-Cas9 mechanism: a guide RNA (gRNA) directs the Cas9 protein to a particular DNA sequence, where it chops the strand. After that, the cell fixes the damage, either causing the gene to malfunction or enabling researchers to introduce a corrected form. It helps connect what we study in class with actual medical advancements and effectively illustrates the mechanism underlying treatments like Casgevy.

 

CRISPR Gene Editing can have Unwanted Effects

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On April 7, 2025

In Student Post

A group of researchers at the University of Zurich have completed a study to test whether CRISPR gene editing technology can be used to correct the DNA sequence error in people with chronic granulomatous, a rare genetic disease that causes white blood cells to be unable to kill certain pathogens. They found that the technology was successfully able to insert the two nitrogenous bases, that are missing in people with this disease, into the DNA sequence. While this process was successful, they also found that, at the same time, it caused further damage to the DNA. 

After performing the gene editing process, the scientists found new defects in the newly repaired cells. In certain cells, the entire section of the DNA where the editing took place was missing. This is due to the NCF1 gene and its characteristics. It shows up three times in the DNA; once as an active gene, and twice as pseudogenes, which are sections of DNA that resemble active genes but are in fact nonfunctional. The CRISPR technology cannot distinguish between the two versions of the gene and therefore ends up editing multiple portions of the DNA, resulting in gene segments being misaligned or missing. The consequences of such errors are still not fully understood and can be unpredictable. Therefore medical professionals are hesitant to use this method of treatment for chronic granulomatous disease. Other research teams have continued this work to find a safer method of treatment using CRISPR. Do you think that CRISPR should be used to cure diseases like chronic granulomatous despite possible risks? 

DNA Structure+Key+Labelled.pn NoBB

Model of DNA Structure

This connects to the AP Biology subjects of DNA structure and function. The CRISPR technology performs edits to DNA sequences such as adding or removing certain nitrogenous bases, which is closely related to DNA structure. It also relates to DNA function as changing the sequence of the DNA will alter what the DNA codes for. This changes how certain portions of DNA affect cell processes by, for example, producing different proteins.

How CRISPR is Supercharging Crops

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On April 7, 2025

In Student Post

Scientists at the Carl R. Woese Institute for Genomic Biology at the University of Illinois have made a breakthrough using CRISPR/Cas9 to enhance gene expression in rice by altering its upstream regulatory DNA. This approach increases photosynthetic efficiency and could lead to major advances in sustainable agriculture.

Usually, CRISPR is used to knock out genes, but this research boosts gene expression instead. The team focused on a gene called PsbS, which plays a key role in photoprotection (helping plants balance light absorption for efficient energy use). By flipping the regulatory DNA upstream of the gene, they triggered a significant increase in its expression. This method left most other genes unchanged, minimizing unintended effects.

Rice provides 20% of the world’s calories, so even small improvements in its growth efficiency could have large global impacts. Unlike genetically modified crops, this method does not introduce foreign DNA, which eases regulatory concerns and making adoption by farmers faster.

In AP Biology, we learn that gene regulation occurs at the transcriptional level and also after transcription, which means that modifications to promoters, enhancers, and silencers can directly affect gene activity. This research aligns with the concept of epigenetic regulation, which refers to changes in gene expression that don’t involve altering the DNA sequence itself. The CRISPR-based strategy used in this study is an example of how epigenetic mechanisms can be used to modify plant traits without changing the plant’s DNA structure, which makes this method valuable for sustainable agriculture.

Additionally, this research illustrates how photosynthesis itself is a complex process involving both light-dependent and light-independent reactions. The CRISPR modification indirectly boosts photosynthetic efficiency by enhancing a plant’s ability to handle the absorption of light, preventing damage to the photosystem and ultimately improving the plant’s growth and productivity. The role of light in photosynthesis is a core principle in AP Biology, and this research builds on that by demonstrating how plant genes can be modified to enhance energy efficiency.

This discovery opens the door for future applications in climate-resistant crops, higher-yield wheat, and drought-tolerant corn. Scientists are already exploring ways to apply similar CRISPR-based enhancements to other frequently used crops, such as maize and soybeans.

I’d be open to eating CRISPR-edited rice since it enhances natural genes without adding foreign DNA. This research interests me because it connects to what I’ve learned in AP Biology about gene regulation and photosynthesis. I think focusing on modifying existing genes is a smart way to improve crops while avoiding GMO concerns.

Would you eat CRISPR-edited rice? Should scientists focus on enhancing natural genes instead of adding foreign DNA?

Green rice sheaves planted in a paddy field with long shadows at golden hour in Don Det Laos Rice can come in brown, white, red, and black colour.

CRISPR: Gene Editing and Its Ethical Dilemmas

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On March 26, 2025

In Student Post

CRISPR: Revolutionizing Gene Editing and Its Ethical Implications

The revolutionary technique known as CRISPR-Cas9 has revolutionized the study of genetics in recent years. With the use of this potent instrument, researchers can precisely alter the DNA of living things, creating new opportunities in fields such as agriculture and medicine. But great power also comes with great responsibility, and the ethical issues surrounding CRISPR are just as important as its possible uses.

Cas9 in complex with sgRNA and target DNA

Understanding CRISPR-Cas9

CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a natural defense mechanism found in bacteria. These organisms use CRISPR sequences to identify and cut the DNA of invading viruses, thereby neutralizing threats. Scientists have harnessed this system, pairing it with the Cas9 enzyme to create a method for editing genes with unprecedented accuracy. The process involves designing a small piece of RNA that matches the target DNA sequence, guiding Cas9 to the exact location for modification.

 

Applications in Medicine

Treating hereditary illnesses is one of the most exciting uses of CRISPR. Scientists are looking at using it to fix the mutations that cause diseases like cystic fibrosis and sickle cell anemia. Instead of just treating symptoms, CRISPR may be able to treat diseases at their root by fixing damaged genes. The safety and effectiveness of these methods are being evaluated in clinical studies, giving patients with diseases that were previously incurable hope.

 

Advancements in Agriculture 

CRISPR is causing a stir in agriculture in addition to medicine. Crops that are more resilient to environmental stressors, illnesses, and pests are being developed by scientists. To solve food security issues in different regions of the world, gene-edited plants, for example, can be designed to have improved nutritional profiles or to tolerate drought conditions. These developments may result in increased crop yields and more environmentally friendly farming methods.

Moral Aspects to Take into Account

Although CRISPR has enormous potential advantages, there are also serious ethical issues. The potential for off-target effects, in which unwanted portions of the genome are changed and result in unanticipated outcomes, is one significant problem.

Cas9 in complex with sgRNA and target DNA A digital sketch depicting a gene-edit

AP Bio Relation

We have studied the mechanisms of transcription, translation, and DNA replication in our AP Biology course. Gaining an understanding of these basic mechanisms is essential to understanding how CRISPR-Cas9 can accurately target and alter particular genes. This technology shows how fundamental knowledge may result in game-changing inventions and is an example of how molecular biology topics we have studied can be applied in real-world settings.The discovery of CRISPR-Cas9 marks a turning point in science by combining enormous promise with difficult moral dilemmas. What do you think about the application of gene-editing technology to people? How does society strike a balance between moral obligation and innovation? Leave a comment below with your opinions.

 

CRISPR: Rewriting the Script in Cancer Treatment

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On January 20, 2025

In Student Post

Cancer continues to impact millions of people each year around the world; however, new breakthroughs in cancer treatment using CRISPR technology are set to transform how we can combat this complex disease. By leveraging CRISPR’s gene-editing capabilities, researchers are unlocking new possibilities to enhance immune responses, optimize therapies, and develop more precise and effective treatments.

A groundbreaking study from Harvard Medical School, led by LaFleur et al. and Milling et al., explored how CRISPR can reprogram T cells to more effectively fight cancer. Cancer cells typically evade the immune system by downregulating antigen presentation or suppressing the immune system. The researchers addressed these challenges by targeting specific genes in T cells to enhance target recognition(improved the T cells’ ability to recognize tumor antigens), increase the length of the immune response, and strengthen activation(amplifying the response on the detection of cancer). These genetically modified T cells show significant improvements in combating cancer in laboratory and preclinical models than the typical T cell. This showcases their potential to develop more effective immunotherapies, especially for cancers resistant to traditional treatments.

CAR T-Cell immunotherapy diagram by (OHC CAR-T team)

Another innovative study by Lei et al. explored CRISPR’s role in enhancing CAR(Chimeric Antigen Receptor) T-cell therapy, a promising approach that modifies a patient’s T cells to target cancer cells. While CAR T-cell therapy has shown success, it faces challenges like limited efficacy against solid tumors, safety concerns, and high costs. CRISPR offers potential solutions by improving efficacy(Enhances T-cell function and persistence through precise gene edits), enhancing safety(disables genes responsible for adverse effects like cytokine release syndrome), and reducing costs(streamlining the manufacturing process to make the therapy more accessible)

This study emphasizes how CRISPR can address existing barriers, making CAR T-cell therapy safer, more effective, and available to more patients.

The potential of CRISPR extends beyond these studies. CRISPR has opened up a new frontier in cancer research by directly editing the genes within cancer cells, disrupting oncogenes, and reshaping immune responses. For example, recent findings revealed that CRISPR can target oncogenes in leukemia cells, reducing their ability to proliferate and making them more vulnerable to existing treatments (Carlo et al.).

These advancements directly connect to what we’ve studied in AP Biology. The role of CRISPR in gene editing demonstrates the power of manipulating transcription and translation, concepts which are directly related to nucleic acids. Additionally, the focus on T-cell activation and immune responses ties into our understanding of cell communication and the immune system’s intricate pathways.

I chose to write about this topic because it represents a deeply personal and hopeful turning point in cancer treatment. My mom battled breast cancer, and seeing her fight the disease made me acutely aware of the challenges cancer patients and their families face.

What do you think about CRISPR’s role in transforming cancer treatment? Could we one day eliminate certain types of cancer altogether? Share your thoughts and let’s discuss!

Unlocking a Cure: CRISPR Takes on Sickle Cell Disease

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On November 5, 2024

In Student Post

Sickle cell disease (SCD) and beta-thalassemia are both caused by mutations in the hemoglobin gene, and can lead to severe anemia. As we learned in AP Biology this year, a single mutation in the amino acid sequence of a protein can have profound effects on its structure and function. In the case of sickle-cell hemoglobin, the mutation involves a change from glutamic acid, a polar amino acid, to valine, a non polar amino acid at the sixth position of the betaglobin chain. This substitution alters the primary structure of the hemoglobin protein and leads to significant changes in its tertiary structure. The introduction of the hydrophobic valine creates an exposed region on the surface of the protein, which promotes aggregation of hemoglobin molecules. These aggregates distort the red blood cells into a sickle shape, causing blockages in blood flow and leading to various health complications. This demonstrates how a single point mutation can disrupt the delicate balance of  a protein’s three-dimensional shape, ultimately affecting its entire functionality.

Normal and sickle red cells

Treatments for these diseases typically require regular blood transfusions, which is not only inconvenient and disruptful for the daily life of patients, but also creates risks such as infections. But recently, researchers have been able to use the gene editing tool of CRISPR-Cas9 to specifically modify patients’ stem cells (specifically the cells that increase blood cells). While modifying, doctors can reactivate fetal hemoglobin production in the body, which normally goes away after birth. Fetal hemoglobin can moderate sickle cell disease through increased oxygen saturation. This process involves taking hematopoietic stem cells (HSC) from either the patient’s bone marrow or blood, and then using CRISPR-Cas9 to edit specific genomes. With this treatment, increased levels of this fetal hemoglobin replace the defective hemoglobin that exists in an adult patient and ultimately alleviate symptoms of both SCD and beta-thalassemia.

This article also discusses specific clinical trials where several patients were enrolled who had a confirmed diagnosis of SCD or beta-thalassemia. During these trials, patients went through a procedure, leukapheresis, to extract their HSCs. Next, isolated cells undergo CRISPR editing in order to correct their genetic mutation or enhance the fetal hemoglobin. The modified cells were then infused back into the patients (this could also involve chemotherapy). These trials were designed to test the safety and success of the procedure. The findings of the trials were encouraging! They found that after the procedure, patients had significant increases in fetal hemoglobin levels, allowing for the symptoms of their condition, like SCD, to lessen. Additionally, some patients reported that they no longer required blood transfusions. The success of these trials are a huge milestone in the treatment for SCD and beta-thalassemia. Only mild negative reactions to the trials were noted, like a fever, and the effects of gene-editing are still being closely monitored to ensure maximum safety for patients.

To conclude, CRISPR technology has extensive potential to address various genetic disorders. As we saw, it creates new ways for treating conditions like SCD and beta-thalassemia. But, it also sets an example for future trials and research for other genetic disorders, like Huntington’s Disease, a neurodegenerative disorder caused by mutations in the HTT gene. The successful application we see in this example of the use of CRISPR may lead to further usage of gene-editing into medical practice. This form of treatment could replace previous ineffective solutions, and transform the well-being of patients with various diseases.

I’m passionate about this scientific breakthrough for sickle cell disease (SCD) and beta-thalassemia because of the amazing ways that CRISPR technology offers hope and shows promising results for symptom relief. I chose to write about this topic because I think it’s incredible that this form of gene editing could not only help patients managing SCD and beta-thalassemia, but thousands of patients dealing with a vast variety of diseases.

What are your thoughts on CRISPR and its potential impact on genetic diseases? Do you think we’ll see more advancements like this in the near future? I’d love to hear your opinions in the comments!

Could Gene Editing be the Key to Perpetual Virus Resistance?

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On May 3, 2024

In Student Post

Influenza viruses have spread rapidly despite the vaccines many of us, humans, get (I, for one, just had the flu despite being vaccinated). Vaccines help our bodies recognize certain pathogens and create baseline antibodies to help neutralize them, but, as I learned in AP Bio class, mutations randomly happen. Not only is this genetic variation the key to natural selection in nature, but also for viruses (though viruses also often use the recombination process). As host organisms work as the viruses’ environment that they are trying to survive and reproduce in, natural selection could choose the viruses with mutations that are not recognized by our immune system from the vaccine and potentially create a new virus strand our vaccine is ineffective against.

Potentially more effective and permanent than vaccines, scientists are now exploring gene editing. A step up from the human interference in artifical selection that we learned in AP Bio, where humans choose to breed organisms with specifc traits to create ideal offspring, gene editing changes the organisms themselves. Typically thought of with genetically modified organisms (GMO) referring to plants and plant-based foods, gene editing can also be done on animals.

Take, for example, genetically-modified chickens that protect against avian influenza infections that have run throughout poultry farms at devastating costs. Since the ANP32A gene in chickens codes for the protein that influenza viruses rely on to successfully hijack cells, scientists edited that gene with CRISPR molecular scissors. As the protein is absolutely essential to the virus hijacking chicken cells, no simple mutations should be enough to override the gene editing; thus, chickens should theoretically be permanently resistant to the virus.

CRISPR-Cas9 Editing of the Genome (26453307604).jpg

In multiple studies done, this permanent resistance was almost the case: every typical chicken got the flu when closely exposed to high levels of it (at least 1000 infectious particles), whereas genetically-modifed chickens very rarely got it. In the first study, ten out of ten typical chickens got it, while just one out of 10 edited chickens got it and also at a lower level. In another experiment with an astounding 1 million infectous particles in two separate incubators, all of the typical chickens got it in both incubators and none of the modified chicken got it in one of the incubators, but five out of ten got it in the other. As it turns out, viruses in the latter incubator adapted to use proteins very similar to the protein the edited gene eliminated. There are two proteins very similar to the eliminated protein in chickens, so, to create full flu resistance in chickens, those two genes would need to be edited as well, researchers confirmed. However, editing those genes may hurt chicken development.

Chickens are everywhere, vital to many people’s diet, and can pass the flu to pigs and even us. If we can make chickens resistant to the flu, it could do us and our world wonders — plus, who knows where we will go from there!? Thus, I believe researchers should focus on figuring out if they can edit those three genes in chickens without hurting their development and how to create resistance with this incredible gene-editing ability if not.

We need to make use of our incredible technologies to limit illnesses and improve society; do you have any thoughts on gene editing or possibly even how we can maximize its potential to practically accomplish this task?

Hope for Solving CRISPR Gene Editing’s Dangerous Side Effects: The ICP

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On May 3, 2024

In Student Post

While CRISPR,  “a technology that research scientists use to selectively modify the DNA of living organisms”, is an incredible advancement for humanity, it is far from perfect. In some treatments, the CRISPR treated cell or packaged CRISPR components are injected into patients with the goal of repairing diseased cells using precise gene edits. Gene therapies utilizing CRISPR have the potential to unintentionally induce “bystander” edits in various regions of the genome, occasionally resulting in the onset of new cancers or other diseases.  The intricacy of bodily tissue contains thousands of different cell types, which causes problems for scientists’ ability to correctly implement CRISPR technology.

CRISPR-Cas

Researchers from the University of California San Diego have developed new genetic systems to essentially fact check CRISPR gene edits. A sequence analyzer was made by this research team that is able to track on and off target mutations and the ways the genes are inherited from one generation to the next. Another system made called the Integrated Classifier Pipeline or ICP is able to reveal specific categories of mutations resulting from CRISPR editing. The ICP was developed in flies and mosquitoes, and it produces a “fingerprint” of how genetic materials are inherited. This allows scientists to track mutational edits to its source and risks associated with potentially dangerous CRISPR treatments.

The ICP and sequence analyzer could be the key to understanding how to further propel CRISPR technology and other “cutting-edge next-generation health technologies” to be consistently safe for human use.  According to Bier, a professor in the UC San Diego School of Biological Sciences, the CRISPR editing system can be more than 90% accurate, however, because it encodes ad nauseam its bound to have inconsistencies; The ICP is able to give a “high resolution picture” to describe what is going wrong.

In AP biology we learned about genetics. The bystander effect caused by CRIPSR  reminds me of gene mutations. The bystander effect is when surrounding genetic data of the gene or codons are deleted or rearranged. This is just like ‘normal’ gene mutations caused by errors in gene replication. Insertion, deletion, duplication, inversion, and translocation are all different gene mutations. The mutation’s effects can be silent, with no change to the amino acid; missense, altering one amino acid and potentially changing the protein’s function; or nonsense, causing premature termination of protein translation, resulting in a shorter or typically nonfunctional protein. The CRISPR bystander mutations would theoretically have the same effects as regular gene mutations.

The content that I have learned from AP Biology is setting me up to be able to understand modern complex biology related issues and discoveries that will continue to arise in the future. I wrote about this topic mainly for the bystander effect; I had never heard of the potential for negative side effects as a result of CRISPR treatment, so to learn and write about it was very interesting. Do you think CRISPR is safe to be used at this point? Will the ICP lead to a vast new bio-technology field of medicine? I think that CRISPR could be very useful to cancer patients who are terminally ill or cannot go through other forms of treatment.  The ICP also seems like a promising start to a new age of medicine and science. I  wonder if CRISPR technology could be used for treating plant disease, like the beech leaf disease, killing many trees in New York.

Highly targeted CRISPR delivery advances gene editing

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On April 17, 2024

In Student Post

This article from the University of California Berkeley discusses a breakthrough in CRISPR-Cas9 gene editing technology. Researchers at the University of California, Berkeley, led by Jennifer Hamilton, have developed a method to deliver CRISPR-Cas9 components directly into specific cells in living animals. This advancement could eliminate the need to extract and reinfuse cells, as currently practiced in many gene therapies.

The key innovation involves encapsulating Cas9 proteins and Guide RNAs within membrane bubbles decorated with antibodies. These antibodies target specific types of cells, allowing the CRISPR components to enter and edit the genetic material within those cells. The researchers successfully targeted T-cells in live mice, converting them into cancer-fighting cells, known as CAR T-cells.

CRISPR Cas9

This targeted delivery method offers several advantages over traditional approaches. By precisely honing in on specific cell types, it reduces the risk of side effects and lessens the need for genetic engineering outside the body. Furthermore, the encapsulated Cas9 proteins have a shorter lifespan, decreasing the likelihood of unintended genetic modifications.

This breakthrough represents a significant step forward in the field of gene editing, with the potential to revolutionize the treatment of various genetic disorders and diseases.

In AP Bio we learned about RNA processing; gene editing is similar to RNA processing in which segments of RNA (introns) are cut from the RNA while exons are spliced together. This process mirrors the artificial editing that humans developed to insert, delete, or modify genes with precision.

 

 

 

 

CRISPR and the Battle Against Sickle Cell Anemia

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On April 17, 2024

In Student Post

File:Sickle Cell Anaemia red blood cells in blood vessels.png

What is Sickle cell anemia, and why is its treatment so important?

Sickle cell anemia is a genetic blood disorder characterized by the presence of abnormal hemoglobin, the protein in red blood cells responsible for carrying oxygen throughout the body. In individuals with sickle cell anemia, the hemoglobin molecules are shaped like crescent moons, rather than the normal disc shape, giving them the name “sickle cell”. This abnormal shape causes the red blood cells to become rigid and sticky, leading to blockages in blood vessels and reduced oxygen flow to tissues and organs, as shown in the image above. As a result, individuals with sickle cell anemia experience episodes of intense pain, fatigue, jaundice, and susceptibility to infections. Sickle cell anemia is a lifelong condition with no cure, but various treatments exist.

What is CRISPR, and how can gene editing therapy help those with sickle cell anemia?

File:CAS 4qyz.png

CRISPR is a groundbreaking gene-editing tool that utilizes a naturally occurring bacterial defense mechanism, specifically Type-I CRISPR RNA-guided surveillance complex (shown above), which functions like molecular scissors, cutting DNA strands at precise locations. By incorporating a synthetic guide RNA that matches the target DNA sequence, scientists can direct the Cas protein to specific genes within a cell. Once bound to its target, Cas initiates a process that either disables the gene or introduces desired modifications.

In December of 2023, the FDA approved for this tool’s use in the treatment of sickle cell anemia. Dr. Stephan Grupp, chief of the cellular therapy and transplant section at Children’s Hospital of Philadelphia, explains the new treatment, stating that: “It is practically a miracle that this is even possible.” Developed by Vertex Pharmaceuticals and CRISPR Therapeutics, this therapy, known as Exa-cel or Casgevy, utilizes CRISPR technology to correct the genetic mutations underlying sickle cell anemia. Individuals like Haja Sandi, grappling with frequent and excruciating pain, view this transformative treatment as a beacon of hope. In her search for CRISPR treatment, Sandi told the New York Times, “God willing, I will go forward with it.”

However, the path to widespread implementation still faces many obstacles, including the complicated and costly procedures involved, limited availability at medical centers, and struggles in securing insurance coverage.

As the healthcare community navigates the logistical complexities of the treatment, the introduction of gene-editing technology marks a significant milestone in the ongoing battle against sickle cell anemia. Ultimately, this new treatment for sickle cell sets the stage for potential advancements in treating other genetic disorders, possibly leading us to a much brighter future.

What are your hopes and/or concerns regarding the future of gene editing and its potential impact on society? Comment below!

Ethical and Scientific Limitations of CRISPR Gene Editing

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On May 7, 2023

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The Third International Summit on Human Genome Editing issued a closing statement a few weeks ago calling for a pause on human genome editing – not permanently as some activists had hoped on ethical grounds, but instead for the near future because the technology is not currently sufficiently advanced as to ensure success. Gene editing involves editing embryos outside the womb and then implanting them to establish pregnancy. In addition to the numerous ethical concerns, such as a pathway to eugenics that the technology might lead to, the summit decided that the risks are simply too great at the present time.

CAS 4qyzThis is because the edits made can result in unintended – and sometimes dangerous – consequences for the embryo that traditional DNA screenings may not pick up on. Gene editing works by unraveling the double helix with helicase (just like in DNA replication), cutting the DNA strand with an enzyme, and then having the cell’s own mechanisms, such as primase and DNA polymerase, combined with the new “blueprint” for DNA,  tell the cell the order the nucleotides are placed in and complete the double helix again to form a complete, but modified, DNA strand. However, sections of DNA can be permanently lost or mistranscribed in the process, resulting in genetic disorders or cell malfunction, including cancers. These are similar to the risks that occur during DNA replication and the general life of the cell, but are significantly more likely to occur. Furthermore, mosaicism, often seen on small levels like calico cats (where different cells receive different activated genes than others), can occur on a massive scale, where some cells receive edits and others don’t, leading to health problems down the road for the embryo, if it survives at all.

As a result, the summit, composed of the world’s leading experts in CRISPR technology and research, decided to enact a pause on human genome editing for now. As the technology advances and is made safer, however, they claim that they will reconsider it. Until then, the use of CRISPR is limited to other organisms, such as plants and lab animals.

Overcoming a Critical Limitation of CRISPR

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On April 23, 2023

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Recent research demonstrates that CRISPR Spherical Nucleic Acids (SNAs) can be delivered across the cell membrane and into the nucleus, all while retaining bioactivity and capability of gene editing. Gene editing is technology which allows a scientist to change an organism’s DNA. 

The work displayed in this article builds on a 25-year study to uncover the properties of SNAs and the factors that distinguish them from the blueprint of life. SNAs are structures typically composed of spherical nanoparticles covered with DNA or RNA, giving them chemical and physical properties different from those forms of nucleic acids found in nature. 

Core-filled and Core-less Spherical Nucleic Acids 01

A variety of SNAs exist, with cores and shells of different chemical compositions and sizes. SNAs are also now being evaluated as potent therapeutics in human clinical trials, such as trials for brain cancer and skin cancer. 

According to nanotechnology pioneer Chad A. Mirkin, “these novel nanostructures provide a path for researchers to broaden the scope of CRISPR utility by dramatically expanding the types of cells and tissues that the CRISPR machinery can be delivered to.” “We already know SNAs provide privileged access to the skin, the brain, the eyes, the immune system, the GI track, heart and lungs. When this type of access is coupled to one of the most important innovations in biomedical science in the last quarter-century, good things will follow.”

Mirkin’s team used Cas9 (protein required for gene editing) as the core of the structure, and attached DNA strands to the surface to form a new type of SNA. These SNAs were also preloaded with RNA capable of performing gene editing and fused with peptides to control their ability to navigate compartmental barriers of the cell, making it the most efficient. In AP Biology, we learned that peptides are molecules containing two or more amino acids. Peptides that contain several amino acids are called polypeptides or proteins. These SNAs effectively enter cells without the use of transfection agents, and display high gene editing efficiency between 32% and 47% across several human and mouse cell lines. 

We Live In a Time Where We Can Hack and Edit The DNA In Diseases, and We Have Only Just Begun…

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On April 23, 2023

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CRISPR gene editing, (Clustered Regularly Interspaced Short Palindromic Repeats), is a relatively new biological technology that allows scientists to fix unimaginable flaws with an unprecedented minimal risk of off-target effects. This advanced technology aligns perfectly with our current unit of DNA replication and Gene expression/replication, so it should be a good review to keep reading.

CRISPR gene editing has two main components; the Cas9 protein and a guide RNA (gRNA). The Cas9 protein acts as the Helicase, cutting and unzipping the DNA strand. The gRNA is designed to recognize a specific sequence in the DNA of a cell. Once the DNA is cut, the cell uses a homologous DNA template to repair the break in the DNA molecule. The template DNA, Homology Directed Repair (HDR), is designed to carry the desired genetic modification and incorporate it into the DNA through the natural DNA repair mechanisms. This process alters or even adds new genetic information to the organism. For example, researchers from UT Southwestern Medical Center used CRISPR to treat Duchenne muscular dystrophy (DMD). A genetic disease that causes muscle degeneration and weakness. The team used CRISPR to delete the gene responsible for producing a toxic protein that causes DMD. They then replaced the missing gene with a shorter, functional version, which allowed the muscles to regenerate and become stronger.

CRISPR illustration gif animation 1

This advanced technology has been used to increase crop yield from various crops. In California it was used to create more drought resistant rice. In another state, it was used to eliminate browning of red apples. This process is becoming increasingly useful and popular because of its safety. The gRNA can be designed to target a very specific sequence of DNA, which means that scientists can modify genes with precision and accuracy. This specificity also reduces unintended genes, which remains to be a large concern for other gene-editing processes. This technology has enormous potential in the science world and can safely guide us into disease treatments, agricultural efficiency, and advanced biological research.

DCas SAM system

CRISPR Gene and what it’s about

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On April 23, 2023

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The CRISPR gene isn’t something that everyone in the world knows about. So what is it? CRISPR stands for  – clustered regularly interspaced short palindromic repeats. This obviously still won’t help to make sense onto what this is. This gene is used in gene editing. Gene editing is used to make new DNA for any organism. According to the article, it helps with adding, removing, or altering genetic material. CRISPR is a new and more efficient way for gene editing. CRISPR has been used in bacteria when fighting against viruses. When the viruses attacks the first time, the bacteria captures the viruses DNA and creates CRISPR arrays which will then remember the virus the second time and fight it off. Researchers then use the CRISPR as RNA to cut off pieces of DNA with the help of the CAS-9 enzyme. Gene editing and the CRISPR gene help with treatment and help prevent diseases to spread in organisms.

According to this article, there are three ways for the CRISPR gene to work. It can disrupt the DNA sequencing. Then it can also delete a fragment of DNA. The last thing it can do is correct/insert. It can add new DNA or it can make edits to the DNA.

According to this article, the CRISPR gene might be able to be used in things beyond the gene editing world. It might be able to help with quick research and findings for things like cancer and other diseases. Feng Zhang is trying to spread this technology across the world so that they can use this new technology to help with things like this.

This also relates to what we are learning in class this year because we are also talking about gene expression and how it works. We learned about transcription and translation. Transcription is the synthesis of RNA with the use of DNA. Then Translation is the synthesis of the protein by the RNA. All of this ties to the gene editing with the CRISPR gene because the CRISPR gene is another wya that the DNA is edited/corrected. It is a much quicker and more efficient way that might be really helpful going forward.

CRISPR-Cas9 mode of action

Can Technology Ketchup To These Super Tomatoes?

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On March 30, 2022

In Student Post

Sicilian Rouge tomatoes are one of the first foods made with CRISPR-Cas9 technology to be sold to the public. An article by Emily Waltz, of Scientific American, goes in depth on how these tomatoes are taking Japan by storm. Sanatech Seed, a company based in Tokyo, has edited the tomatoes to have a large amount of GABA(γ-aminobutyric acid).  According to the company, GABA supposedly lowers blood pressure and promotes relaxation when ingested orally.

In Japan, GABA is a popular addition to many foods, drinks and other products such as chocolates. Hiroshi Ezra works as both the chief technology officer at Sanatech and a plant molecular biologist at the University of Tsukuba. He says that “GABA is a famous health-promoting compound in Japan. It’s like vitamin C…That’s why we chose this as our first target for our genome editing technology. “

 

CRISPR has been used in a myriad of ways by plant bioengineers. Non-browning mushrooms and drought-tolerant soybeans are just a few examples of this. However, Sanatech’s Sicilian Rouge tomato was the first CRISPR-edited food known to be commercialized.

 

But what is CRISPR and why has it become so popular? Yourgenome.org effectively explains what the different parts of the CRISPR-Cas9 technology do. The system is made of two parts: the enzyme and RNA. The enzyme is called Cas9 and its role in gene editing is to ‘cut’ the specific genome in strand of DNA so that the mutation can be made. The RNA acts as a guide for the enzyme, which is why it is called gRNA. The piece of RNA is made of an approximately 20 base sequence that is a part of the longer RNA ‘scaffold’. When the strand binds to the DNA the 20 base sequence guides the Cas9 to the part of the genome that is meant to be cut. The scaffold is able to find the correct genome because its bases are made to be specifically complementary to the target genome. Once the genome is cut the cell recognizes the cut in the DNA and repairs it. It is when this repair takes place that the changes/mutations to the genome occur. 

4.3. The CRISPR Cas 9 system III

The processes of CRISPR are similar to what we learned about in biology too. During DNA replication, small complementary strands of RNA act as primers so that DNA polymerase can add to anc continue the chain. DNA polymerase also ‘proofreads’ strands of DNA for any mistakes which it would cut out and replace with the correct nucleotides. The Ligase then reforms the phosphodiester bonds which hold the nucleotides together. This process of error correction is what takes place once the Cas9 cuts the genomes.

 

Another type of DNA editing is called TALENs or transcription activator-like effector nucleases. A company called Calyxt commercialized TALENs through their genetically edited soybean oil that is free of trans fats. Gene editing hasn’t only been bound to plants, but also animals too. In October of last year Japan approved CRISPR two gene-edited fish. One was an edited tiger puffer which “exhibits depressed appetite suppression”. The other was a Red Sea bream which was edited to have “increased muscle growth”.

 

From super-crops to super-fish, it appears as though there are no limits for CRISPR in our daily lives. It’s amazing how precise technology has allowed us to alter the nutrition of the food we eat. I wonder what other possibilities lie in the future of CRISPR and how they will affect our society.

Unnatural Selection: The Future of The Future?

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On March 20, 2022

In Student Post

Imagine it’s Saturday night, you are snowed in until the morning and you need a way to pass the time. Like many people, you resort to Netflix. Upon browsing through the vast selection of horror, comedy, and romantic films, you decide you are in the mood for a documentary. Scrolling through the options, you stop at a title that grabs your attention: Unnatural Selection.

Since you are an AP Biology student, you immediately connect the words “Natural Selection” to the work of Charles Darwin, the study of genetics, and most importantly: evolution. In brief, natural selection is the survival and reproduction of the fittest, the idea that organisms with traits better suited to living in a specific environment will survive to reproduce offspring with similar traits. Those with unfavorable traits may not be able to reproduce, and therefore those traits are no longer passed down through that species. Natural selection is a mechanism for genetic diversity in evolution, and it is how species adapt to certain environments over many generations.

If genetic diversity enables natural selection, then what enables unnatural selection? Well, If natural selection eradicates unfavorable traits naturally, then unnatural selection essentially eradicates unfavorable traits or promotes favorable traits artificially.

The Netflix docuseries “Unnatural Selection” focuses on the emergence of a new gene-editing technology named CRISPR (an acronym for “Clustered regularly interspaced short palindromic repeats”). CRISPR is a revolutionary new method of DNA editing, which could help cure both patients with genetic diseases and patients who are at risk of inheriting unwanted genetic diseases. The two pioneers of this technology, Emmanuelle Charpentier and Jennifer Doudna, recently won Nobel Prizes in Chemistry for their work on CRISPR.

CRISPR illustration gif animation 1

Animation of CRISPR using guide RNA to identify where to cut the DNA, and cutting the DNA using the Cas9 enzyme

CRISPR works with the Cas9 enzyme to locate and cut a specific segment of DNA. Scientists first identify the sequence of the human genome, and locates a specific region that needs to be altered. Using that sequence, they design a guide RNA strand that will help the Cas9 enzyme, otherwise known as the “molecular scissors” to locate the specific gene, and then make precision cuts. With the affected region removed, scientists can now insert a correct sequence in its place.

Using the bacterial quirk that is CRISPR, scientists have essentially given anyone with a micropipette and an internet connection the power to manipulate the genetic code of any living thing.

Megan Molteni / WIRED

CRISPR is just the beginning of gene editing, introducing a new field of potential gene editing research and applications. But with great power comes great responsibility — and great controversy. Aside from the obvious concerns, people speculating the safety, research, and trials of this new treatment, CRISPR headlines are dominated by a hefty ethical dilemma. On one hand, treating a patient for sickle cell anemia will rid them of pain and suffering, and allows their offspring to enjoy a normal life as well. However, by eliminating the passing down of this trait, sickle cell anemia is slowly eliminated from the human gene pool. Rather than natural selection choosing the path of human evolution — we are. We are selecting which traits we deem “abnormal” and are removing them scientifically. Although CRISPR treatment is intended to help people enjoy normal lives and have equally as happy children, putting evolution into the hands of those evolving can result in more drastic effects in the future.

For our generation, CRISPR seems like a magical cure for genetic diseases. But for future generations, CRISPR could very well be seen as the source of many problems such as overpopulation, low genetic diversity, and future alterations such as “designer babies.” Humans have reached the point where we are capable of our future. Is CRISPR going to solve all of our problems, or put an end to the diverse human race as we know it? Comment how you feel down in the comments.

 

CRISP[ie]R Corn Kernels?

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On March 20, 2022

In Student Post

Corn is unique in the way that its genome is highly complex, thus causing it to be very difficult to edit those genes with technology such as CRISPR. CRISPR is an advanced technology that is used to find a specific portion of DNA in a cell and then it alters that piece of DNA. To learn more about CRISPR, click here.

CRISPR CAS9 technology

In a recent study at Cold Spring Harbor Laboratory, researchers attempted to modify the growth of stem cells and promotor regions in corn using CRISPR. Thousands of years ago, corn was just a plant covered in weeds that formed very few kernels on its surface. Through gene editing technologies, scientists were able to transform the hopeless plant into a delicious vegetable with juicer kernels bursting from all surfaces. To increase the number of corn kernels 0n the surface of the plant, Professor David Jackson along with Lei Liu worked in collaboration with Professor Madelaine Bartlett from the University of Massachusetts Amherst. They were one of the first groups to tackle the editing of corn’s complex set of DNA.

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We are currently learning in AP Biology how DNA is replicated and can be altered. In replication, DNA is first untwisted by a helicase enzyme. Similarly, CRISPR uses an enzyme called Cas9 that unzips the DNA. This allows for the newly created strand of RNA to be matched to the target DNA. The Cas9 then cuts the DNA strand which causes the cell to attempt and put the strand back together and this results in new genes being formed because the DNA sequence is altered. This is just like how in replication, the DNA polymerase adds nucleotides to an existing strand of DNA. This video also provides a great visual description of how CRISPR can edit existing genes.

Since corn is a plant, it consists of plant cells that have a much stronger cell wall than animal cells do. This makes it harder for the CRISPR to access the cell’s DNA and make edits. CRISPR can be used to disrupt genes and eliminate them, as well as help the promoter regions which activate the genes instead. Corn kernel development depends on the genes supporting stem cell growth. They experimented by targeting random areas of the promoter to see which part will change the number of kernels on the cob.

Ontario-Corn-field 03

As a veggie-lover myself, I am so glad that these new gene-editing procedures allow for fuller, juicier corn kernels. Not only is this beneficial to those who eat corn on the cob or choose to enjoy a moist slice of cornbread, but also to those who love to sit down with a big bowl of popcorn to watch a movie. If a vegetable with such complex genes as corn is able to be improved, imagine what the future holds for other plants yielding yummy additions to our diets!

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