In this article, we will explore gene therapy and its revolutionary potential in the field of medicine. Gene therapy is presented as a direct approach to treating genetic diseases and other medical conditions. This field, which also includes related techniques such as gene editing, is based on an understanding of how genes work and how changes in them can affect our health. |
Gene therapy is a direct way to treat genetic conditions as well as other conditions. There are also other related approaches like gene editing. There are many different versions and approaches to gene therapy and gene editing. [1] It all rests on understanding how genes work and how changes in genes can affect our health. Researchers all over the world are studying many different facets of gene therapy and gene editing. It’s a Healthcare Game-Changer. Gene therapy has emerged as a transformative topic in medicine, with the potential to cure a wide range of hereditary illnesses and perhaps increase human longevity. In this essay, we'll debunk the notion of gene therapy, look at how it works, and consider its far-reaching consequences for the future of healthcare.
Figure 01: How its work? (Source NIH)
There are a variety of types of gene therapy products, including:
Plasmid DNA: Circular DNA molecules can be genetically engineered to carry therapeutic genes into human cells.
Viral vectors: Viruses have a natural ability to deliver genetic material into cells, and therefore some gene therapy products are derived from viruses. Once viruses have been modified to remove their ability to cause infectious disease, these modified viruses can be used as vectors (vehicles) to carry therapeutic genes into human cells.
Bacterial vectors: Bacteria can be modified to prevent them from causing infectious disease and then used as vectors (vehicles) to carry therapeutic genes into human tissues.
Human gene editing technology: The goals of gene editing are to disrupt harmful genes or to repair mutated genes. [3]
Patient-derived cellular gene therapy products: Cells are removed from the patient, genetically modified (often using a viral vector) and then returned to the patient.
Gene Editing Technologies: Precision at the DNA Level
The introduction of gene editing tools such as CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is one of the most significant advances in gene therapy. [5] These techniques allow scientists to accurately change DNA sequences, allowing them to modify genes responsible for a variety of disorders.
Gene editing entails splicing gene sequences, which entails removing and rearranging certain DNA sequences. This procedure is similar to making exact changes to a text document. Scientists can identify the faulty genes that cause hereditary illnesses and use CRISPR or other comparable technologies to make targeted changes. Inserting, removing, or changing certain genomic sequences can be used to either fix a genetic mutation or interrupt the production of a dangerous gene. [7]
Figure 02: The CRISPR tool kit for genome editing and beyond
Gene regulation and transcription are also important in gene therapy. Rather of directly changing the DNA sequence, some gene treatments try to modulate gene expression. By adding chemical markers to the DNA, techniques such as methylation can be used to quiet or "turn off" specific genes. These strategies aid in regulating gene expression and treating disorders caused by overactive genes. [12]
Treating Genetic Conditions with Gene Therapy
The approval of ground-breaking medicines such as Luxturna, Zolgensma, and Kymriah in 2017 was a watershed moment in gene therapy. [9] These treatments have changed the therapeutic landscape for illnesses such as blindness and leukaemia, giving patients fresh hope.
Luxturna, for example, is a gene therapy used to treat a rare form of hereditary blindness caused by RPE65 gene abnormalities. A modified virus is used as a vector in this therapy to transport a healthy copy of the RPE65 gene into the patient's retinal cells. [11] This restored gene permits cells to generate a previously missing functional protein, thereby enhancing eyesight. [14]
Zolgensma is also used to treat spinal muscular atrophy (SMA), a debilitating hereditary condition. It operates by employing a viral vector to deliver a functioning copy of the SMN1 gene to motor neurons, essentially compensating for the faulty gene's absence. [10]
Figure 03: Gene Therapy Successes
Kymriah, on the other hand, is a CAR T-cell therapy that is utilised in the treatment of specific kinds of leukaemia and lymphoma. [16] It entails collecting a patient's immune cells, genetically altering them to more efficiently target cancer cells, and then reinfusing them into the patient's body to fight the disease. [8]
The use of gene editing tools, including viral vectors, to replace or augment the defective genes responsible for the illness is a common thread across these treatments. [13] The objective is to 'switch off' or compensate for disease-causing genetic abnormalities, resulting in dramatic improvements in the health and quality of life of patients. [4]
The Future of Gene Therapy and Human Lifespan
Gene therapy has enormous potential and offers the prospect of revolutionising healthcare in ways we can only begin to envisage. While we have achieved significant progress, it is critical that we limit our expectations regarding its influence on human lifetime.
Figure 04: Future of Gene therapy
Although gene therapy has the potential to treat a wide range of hereditary illnesses, it is not a cure-all for all health problems. [15] Many illnesses are the result of a confluence of hereditary, environmental, and lifestyle factors. As a result, while gene therapy can treat genetic components of disorders, other variables must also be taken into account. [6]
Future human longevity estimates in the context of gene therapy remain hypothetical. While some experts believe that gene therapy might help people live longer, healthier lives, it is unlikely to be the only factor influencing human longevity. Other factors, like as medical advancements, diet, and lifestyle choices, will continue to play important roles. [17]
Furthermore, the ethical, regulatory, and accessibility issues of gene therapy must be carefully considered to guarantee that this technology serves mankind as a whole. Ensuring fair access to these medicines, as well as addressing any concerns about unintended effects, are key parts of gene therapy's continuous development. [2]
Conclusion:
Gene therapy is a revolutionary discipline of medicine that has the potential to improve healthcare by addressing the underlying causes of hereditary illnesses. It entails precise DNA sequence editing, gene control, and the use of viral vectors to treat a variety of illnesses. While gene therapy gives promise for enhancing the quality of life of people with genetic illnesses, its impact on human longevity is unknown and impacted by a variety of circumstances. As we continue to study and expand this sector, we must keep ethical and accessibility concerns in mind in order to realise its full potential for the benefit of all. Gene therapy is undeniably transformative, but the complete tale is still being told.
About the Author:
Maheen Javed, M.D. graduated as a medical doctor in 2020 with experience in medical research, medical writing and other diverse areas in the medical field. She currently practices in a hospital and works as a professional medical writer and researcher, writing technical articles on a wide variety of topics in the medical field, such as mental health, diabetes, women's health, cancer research, psychiatry, neurology, surgery and mental health.
About the editor:
Brian Hoy has over 20 years of experience in the medical device industry and business formation, supporting the full lifecycle with global scope. Brian consults for industry and provides general advisory and off-hours support.
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