Gene Therapy: A Scientific Phenomenon - By Saanvi Tatipalli, Tanushka Mithun and Sridatri Bandaru
Abstract
Gene therapy is a relatively recent idea that could revolutionize our world. It was
discovered in the late 20th century and still continues to be explored today. It has various
procedures that can be conducted, all revolving around the idea that it is possible to replace or overpower a certain gene from the human DNA and improve an individual’s genetic structure. Many scientists have found that this can be a potential cure for many genetic disorders and may change the future of the medical world. However, the procedure can be complicated and can risk the recipient’s life if any minor mistake is made. Scientists have yet to discover many aspects of gene therapy. Hopefully, in the future, they will be able to use this remedy to successfully cure diseases that were once incurable.
History
Humans have discovered many influential phenomena about gene therapy that have led it to become the 3.8 billion dollar industry that it is today (Reportlinker). One of the many
discoveries that helped introduce the idea of gene therapy was made in 1953 at King’s College in London, where scientists discovered DNA in the shape of a double helix. Many more revelations were made in the coming years. These led to a discovery in the mid-1960s, where the bases of the amino acids were found, and as a result, many technological advancements were made. Soon after, in 1973, researchers found out how to introduce a replicated strand of one’s DNA into another being’s body.
These fascinating moments in history all led to an extremely influential discovery in 1990
when Michael Blaese and French Anderson used the new viral vector technology (a tool created to contain the healthier gene) to conduct the very first clinical trial of gene therapy on two patients with severe combined immunodeficiency (bluebirdbio). Gene therapy has evolved significantly in the past, and hopefully, scientists will continue to find an extravagant amount of new information about gene therapy in the coming years.
Procedures of Gene Therapy
Though gene therapy may eventually change the way people live, it is currently very
complicated. There are many components that go into this procedure and many things to
comprehend related to how this operation takes place. The first thing to understand is that genes are biological units that define how an individual is built. Some of these genes could be mutated, which could potentially lead to a disorder. Gene therapy is generally used to turn off or replace these genes (“How Does Gene Therapy Work?”). There are two main types of treatment: somatic and germline. In somatic gene therapy, the transferred DNA is from an area of the body that does not produce sperm or egg cells. On the other hand, germline gene therapy focuses on sending the fixed gene to an area of sperm or egg production (YourGenome). This assures that the embryo will be affected by the new gene as well.
Some techniques for conducting gene therapy are gene augmentation therapy, gene
inhibition therapy, and the killing of specific cells with cell suicide. In gene augmentation
therapy, the doctor adds an already functional cell to replace the lost or faulty one. This process only works when the disease is reversible and has only done partial damage to the body. In gene inhibition therapy, scientists send a gene to eliminate the product of another gene. In the killing of specific cells, DNA is made and sent to cause a faulty cell to do apoptosis (cell suicide). This would help eliminate the problem the DNA was causing (YourGenome). Each of these forms serve their own various purposes and have their own benefits and downfalls. These procedures have the same overall process in which viral vector technology is involved. Scientists utilize this technology to send genetic cargo into the designated area. To do so, scientists design the vector to act like a virus in order for it to safely enter into a cell. If a gene is directly inserted into the body, it does not affect the individual in any way. Therefore, gene therapists engineer a vector to carry the gene and deliver it properly. (Nienhuis) As illustrated in Figure 1, the vector is injected into the patient’s body. After this, the vector arrives in the area and delivers the new gene that is in charge of overpowering the faulty one. This process may seem excessive, but gene therapy can impact the recipient in numerous beneficial ways.
Figure 1: The Process of an Adenovirus Vector
This diagram shows the process that the vector follows after being sent into a body. It begins by being injected and travels to the cell. It then delivers the newly functional gene, which
overpowers the malfunctioned gene.
What Gene Therapy Can Cure
There are many cases of genetic disorders affecting countless people across the globe.
Gene therapy can be the solution to the problems caused by these mutated genes. For example, in the past, gene therapy has successfully cured several patients with immune deficiencies. To accomplish this, scientists have removed the damaged stem cells and reinserted them with fixed ones (“Gene Therapy Successes”). Additionally, hereditary blindness, a disorder in which a patient’s eyes are damaged by retinitis pigmentosa, has also been successfully cured with this method. Doctors have a high chance of curing the degenerative forms, where the individual loses their light-sensing abilities (“Gene Therapy”). Furthermore, gene therapy has been successful in curing cases of hemophilia, hereditary cancer, Parkinson’s disease, mesothelioma, and many more genetically inherited disorders (“Gene Therapy Net”). In the future, gene therapy could be a potential cure for a wider variety of genetic deseases.
Risks/Complications
Although gene therapy could benefit individuals with genetic diseases, it may also put
them at high risk. One risk is that it could worsen the symptoms of the genetic disorder that the patient had before attempting gene therapy, or it may cause the symptoms to last for a longer period of time. Currently, some tests suggest that gene therapy can provide serious health risks such as inflammation, toxicity, or cancer. Scientists are working on solutions for this, and due to the fact that gene therapy is still a rather recent discovery, there is still ambiguity on what exactly could go wrong (Genetic Home Reference). Some cases of gene therapy have even left patients in life-threatening conditions and may continue to do so. One obstacle regarding the procedure of gene therapy is that a patient’s immune system may fight off the vector (the virus that contains the improved gene). In other cases, the vector can affect an incorrect gene. This could cause a gene that was once healthy to malfunction, which in turn, may seriously affect the patient in countless hazardous ways, all resulting in unknown symptoms (Genetics Science Learning Center). These symptoms could be fatal, but hopefully, scientists will soon be able to overcome these obstacles.
Conclusion
Gene therapy is a distinctive form of treatment that could solve numerous health
deficiencies. This remedy can be used to replace or turn off specific diseased genes. Scientists are still researching and are hopeful to discover solutions to counteract the insufficiencies of this exhausting process. Gene therapy, a scientific phenomenon, could potentially be the answer to defeating many disorders and could break the boundaries of medicine, saving millions of lives.
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