Gene Therapy

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Gene therapy is a innovative type of cell therapy used to prevent, treat, and even cure genetic diseases by changing the expression of one’s genes. While gene therapy holds great promise, clinical trials are in their infancy and current therapies are primarily experimental.

To reverse disease caused by genetic damage, researchers isolate normal DNA and package it into a vehicle known as a vector, which acts as a molecular delivery engine. Vectors composed of viral DNA sequences have been used successfully in human gene therapy trials.

Researchers are working to develop and optimize vectors (viral and non-viral). Nonviral gene delivery involves complexing DNA with an agent that allows it to enter a cell nonspecifically. DNA delivered in this manner is usually expressed for only a limited time because it rarely integrates into the host cell genome.

WHAT IS GENE THERAPY?

Gene therapy aims to correct genetic disorders by replacing missing or abnormal genes by transplanting normal, healthy genes into cells within the body.

HOW DOES GENE THERAPY WORK?

Gene therapy is the addition of new genes to a patient’s cells to replace missing or malfunctioning genes. 

In general, a gene cannot be directly inserted into a person’s cell.  It must be delivered to the cell using a carrier, called a vector. The vectors most commonly used in gene therapy are viruses. Viruses have a unique ability to recognize certain cells and insert genetic material into those cells.

WHAT TREATMENT METHODS ARE USED?

The following are among gene therapy methods being studied by researchers:

  • Deliver genes that promote the growth of new tissue or stimulate regeneration of damaged tissue
  • Deliver genes that accelerate the destruction of cancer cells or cause cancer cells to revert back to normal tissue
  • Deliver viral or bacterial genes as a form of vaccination
  • Genetically modifying immune cells – immune cells are isolated and then genetically engineered to recognize a specific antigen. When placed back into the patient, these immune cells will attack cells that carry the antigen and produce a disease-fighting product.
  • Gene silencing – an approach used to turn a gene “off” so that no protein is made from it
  • Repairing dysfunctional genes or by providing copies of missing genes –  genes are delivered to the cell using a carrier, called a vector. A target cell is infected with the vector. The vector unloads its DNA cargo, which then begins producing the proper proteins in order to restore the cell to normal.

WHICH DISEASES DOES GENE THERAPY TREAT?

Approximately 4,000 diseases have been traced to gene disorders. Those diseases caused by single gene defects are most likely to be successfully treated by gene therapy.

Patients with the following diseases may be candidates for gene therapy: cancer, Parkinson’s and Alzheimer’s diseases, AIDS, cystic fibrosis, amyotrophic lateral sclerosis (Lou Gehrig’s disease), cardiovascular disease and arthritis.

Digital 3d model of DNA structure