Gene Therapy a Promising Approach in Modern Medicine

Suneel Kumar^*1 , Arvind Singh²

^1,2Department of Genetics and Molecular Biology, SRM University Chennai, India

Corresponding Author

Suneel Kumar, Department of Genetics and Molecular Biology, SRM University Chennai, India, E-mail: sune_kum6@gmail.com

Abstract

Gene therapy is an emerging area in medical science aimed at treating or preventing diseases by modifying genes. It involves inserting, altering, or removing genetic material in a patient's cells. This article reviews the development, types, delivery methods, applications, advantages, challenges, and future outlook of gene therapy. Special attention is given to current technological advances and the ethical implications surrounding this powerful treatment method. Inline references and two informative tables are included for clarity and understanding.

Keywords

Pericardial tamponade; Limited systemic sclerosis; Systemic sclerosis; Recurrent pericardial effusion; Rheumatology; Cardiology; Pericardiocentesis

Introduction

Gene therapy introduces a new direction in treating diseases by targeting their genetic roots rather than just managing symptoms. It has the potential to cure many life-threatening conditions by correcting the underlying genetic errors. Although still under research and development, gene therapy has already been applied to treat some genetic and acquired disorders, demonstrating its clinical value [1].

Historical Development

The origins of gene therapy can be traced back to the 1960s, with the first approved human gene therapy trial taking place in 1990. The patient was a young girl with Severe Combined Immunodeficiency (SCID), who received a functioning copy of the ADA gene, resulting in a temporary clinical improvement [2]. Since then, gene therapy has progressed through decades of clinical and technological advancement. In 2017, the FDA approved Luxturna, the first gene therapy for a genetic eye disease, signaling a significant milestone [3].

Basic Concepts of Gene Therapy

Gene therapy aims to modify or replace faulty genes to treat disease. This is typically achieved by one of three main approaches:

• Gene Replacement: introducing a healthy gene to replace a defective one.
• Gene Inactivation: silencing a malfunctioning gene.
• Gene Addition: introducing a new gene that helps fight disease [4].

The success of these approaches depends on efficient and safe delivery systems, referred to as vectors.

Types of Gene Therapy

Gene therapy can be categorized based on the type of cells being targeted:

Somatic Gene Therapy

Somatic gene therapy modifies genes in non-reproductive (body) cells. The changes are not passed on to offspring. This type is widely accepted and used in clinical trials and approved therapies [5].

Germline Gene Therapy

Germline therapy targets reproductive cells (sperm or egg). The resulting genetic changes are heritable. Due to ethical concerns and potential risks, this type is banned in many countries [6].

Methods of Gene Delivery

Effective delivery of therapeutic genes is essential. The two main categories are viral and non-viral vectors.

Viral Vectors

Viruses are naturally equipped to deliver genetic material. Modified viruses are often used as vectors in gene therapy. Commonly used viral vectors include:

• Adenoviruses
• Retroviruses
• Adeno-associated viruses (AAVs)
• Lentiviruses

Each has different features in terms of efficiency, safety, and duration of gene expression [7].

Non-Viral Methods

Non-viral methods are less efficient but safer. These include:

• Liposomes
• Electroporation
• Gene gun (particle bombardment)
• Direct injection of naked DNA

These methods are used when reduced immune reaction is necessary [8] [Table 1].

Feature	Viral Vectors	Non-Viral Methods
Efficiency	High	Low to Moderate
Safety	Risk of immune response	Generally safer
Duration of Gene Expression	Long-lasting (some vectors)	Often temporary
Integration into Genome	Sometimes integrates (e.g., retroviruses)	Usually does not integrate
Size of Gene Insert	Limited	Can accommodate larger genetic sequences

Source: Compiled from references [7, 8]

Table 1: Comparison of Viral and Non-Viral Vectors

Applications of Gene Therapy

Gene therapy has potential applications in a variety of diseases:

Genetic Disorders

Single-gene disorders are ideal candidates. Examples include:

• Cystic fibrosis: mutation in the CFTR gene.
• Sickle cell anemia: caused by abnormal hemoglobin.
• Duchenne muscular dystrophy: dystrophin gene mutation.
• Thalassemia: errors in hemoglobin genes [9].

Cancer Treatment

In oncology, gene therapy can:

• Introduce tumor-suppressor genes.
• Trigger apoptosis in cancer cells.
• Use CAR-T cell therapy, where T-cells are engineered to target cancer cells [10].

Infectious Diseases

Gene therapy can prevent or suppress infections by:

• Blocking viral receptors (e.g., HIV’s CCR5 receptor).
• Enhancing immune response against pathogens.
• Modifying immune cells for stronger antiviral activity [11] [Table 2].

• Disease	Category	Gene Therapy Strategy
  Severe Combined Immunodeficiency	Genetic Disorder	ADA gene replacement via retroviral vector
  Spinal Muscular Atrophy	Genetic Disorder	AAV vector delivering SMN1 gene
  Leukemia (CAR-T)	Cancer	Genetically modified T-cells targeting antigens
  Hemophilia A	Genetic Disorder	Introduction of factor VIII gene
  HIV	Infectious Disease	Editing CCR5 receptor to prevent viral entry

Source: Based on data from references [9, 10, 11]

Table 2: Examples of Gene Therapy Applications in Diseases

Recent Technological Advances

CRISPR-Cas9 Gene Editing

CRISPR is a powerful gene-editing tool that allows for targeted changes to DNA. Its precision and efficiency make it an attractive method for correcting mutations [12].

Clinical trials are ongoing using CRISPR to treat:

• Sickle cell disease
• Beta-thalassemia
• Certain cancers

Improved Delivery Vectors

Researchers are exploring newer vectors like synthetic nanoparticles and exosomes, which aim to increase safety and reduce immune response [13].

In Vivo Gene Editing

This involves editing genes directly within the patient's body, without removing cells. It offers convenience and efficiency for certain conditions [14].

Challenges in Gene Therapy

Safety Issues

Potential risks include:

• Unwanted immune responses.
• Insertional mutagenesis, where the gene inserts into the wrong location and disrupts healthy DNA [15].

Ethical Concerns

Germline modifications raise significant ethical questions about human enhancement and consent for unborn generations [16].

High Cost of Treatment

Approved gene therapies are often expensive. For example:

• Zolgensma(for SMA) costs over $2 million per dose [17].

This raises concerns about healthcare access and affordability.

Technical Limitations

Issues such as limited vector capacity and difficulty in targeting specific tissues need to be resolved for broader application [18].

Ethical and Legal Considerations

Gene therapy raises important ethical and legal questions that require careful oversight and regulation. It is essential that gene therapy be used strictly for medical treatment, not for enhancing human traits or selecting physical or intellectual characteristics. International organizations such as the World Health Organization (WHO) and UNESCO have established guidelines that highlight the importance of voluntary and informed consent discourage the use of germline editing, and call for the protection of vulnerable populations [19]. These principles are intended to ensure that gene therapy respects human dignity and rights. In addition to international guidelines, national regulatory bodies such as the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) are responsible for reviewing and monitoring gene therapy trials to ensure they meet high standards of safety, effectiveness, and ethical responsibility.

Future Directions

The future of gene therapy appears highly promising as rapid advancements continue to shape the field. One significant area of progress is personalized medicine, where treatments are designed to match an individual's unique genetic profile, increasing both safety and effectiveness. Another important development is the integration of gene therapy with stem cell technology, allowing for the creation of long-lasting and possibly permanent treatments through gene-edited stem cells. In addition, efforts are being made to make gene therapy more accessible worldwide by reducing costs through technological improvements and supportive health policies. Looking ahead, researchers aim to expand the use of gene therapy beyond rare genetic disorders to include more common conditions such as diabetes, Alzheimer’s disease, and heart disease. With continued scientific progress and collaboration, gene therapy may become a standard option in the treatment of both inherited and chronic illnesses.

Conclusion

Gene therapy represents a transformative approach in modern medicine. By addressing diseases at the genetic level, it offers possibilities for permanent cures rather than symptom management. Though there are safety, ethical, and financial challenges, continued progress in research and technology is expected to overcome many of these barriers. Collaboration among scientists, regulatory authorities, and the public will be essential to ensure that gene therapy is safe, ethical, and widely accessible.

Copyright

© 2025 by the Authors & Epic Globe Publisher. This is an Open Access Journal Article Published Under Attribution-Share Alike CC BY-SA: Creative Commons Attribution-Share Alike 4.0 International License. Read More About Open Access Policy.

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