Gene therapy is a process by which a genetic disease in someone is treated by introducing new DNA containing a functional gene that will help correct the mutation caused by the disease. Extremely advanced scientific research and techniques are employed to carefully select the genes required for the therapy that has shown the most promise in treating cystic fibrosis and muscular dystrophy. Depending on the nature of the cells requiring treatment, one of the two types of gene therapy may be used. Somatic gene therapy involves gene manipulation in cells not involved in the reproductive process such as eggs or sperm, while Germline gene therapy relates to cells producing sperm or eggs; the effects of the therapy will be passed on to future generations.
Techniques of Gene Therapy
Gene augmentation therapy: This is used for treating diseases that are a result of a gene mutation that stops the production of a functioning product, for example, a protein. Selective DNA addition is done to introduce a gene that is functional in the cell requiring it. This technique is effective if the disease has not yet caused any irreversible damage.
Gene inhibition therapy: This is a technique that introduces a gene that either inhibits the activity of another gene or interferes with the action of a product of a different gene. The principle of this therapy is to remove the activity of a gene responsible for encouraging disease-related cell growth. This therapy is considered effective for treating cancer, infectious diseases, and genetic diseases caused by gene malfunction. Read more about this treatment at https://www.mybiosource.com/learn/testing-procedures/chromatin-immunoprecipitation
Killing precisely-identified cells: This type of therapy envisages the introduction of a DNA into a diseased cell for the purpose of killing it off. Typically, this is achieved either by a gene that produces a substance toxic enough to kill the target cell or by producing a protein that identifies the diseased cells to the body’s immune system to kill them. The technique demands extremely precise target cell identification to prevent healthy cells being killed.
The Mechanics of the DNA Transfer
The transfer of the DNA containing the gene that is responsible for generating the required protein is done by packaging it into a vector like a virus, plasmid or a bacterium. The task of the vector is to act as a vehicle to transport the DNA section into the genetically diseased cells of the patient. Once the vector reaches the target cells, the normal process of the cell expresses the DNA and starts producing the necessary therapeutic protein for disease treatment.
While the theory of gene therapy sounds very simple, there are quite a few challenges involved. The gene has to be delivered to the proper target cell otherwise an incorrect delivery could result in health issues for the patient. After proper delivery has taken place the gene needs to be activated even in the face of opposition by the cells. The immune system may consider the new gene as potentially harmful and try to fight it. The challenge lies in the gene being delivered in a way that goes unnoticed by the target cell. Also, the function of the existing genes should not be disrupted by the new gene.