Gene Therapy is a medical technique that uses genes or DNA to treat or prevent a disease. Got it, but still what is gene therapy? How does it work? It is still in experimental stage, after being conceptualized in 1972, and having it’s first success in 1990. It is currently used for diseases for which there is no cure, for example, inherited disorders or certain viral diseases, muscular dystrophy and yes certain types of cancer.
The therapy works by introducing a gene or strand of DNA, to a cell to cure the disease or prevent it from happening. Despite being a promising method for treatment of diseases, it is still in its infancy. It may be termed as risky for its effects are not widely known and understood. While every treatment method carries its share of pros and cons, there are several hurdles which need to be crossed for it to become a widely accepted method of treatment.
There are 2 types of gene therapy based on types of cells that are being treated. First is Germline gene therapy, which transfers genes to cells that form eggs or sperms. This way effects of gene therapy are passed on to future generations. Second is Somatic gene therapy, where the gene is not added to a cell which further forms eggs or sperm. this way effects of gene therapy are not passed to future generations.
3 Techniques or methods are used to perform it. Use of a technique depends on the problem or disease to be treated and the final outcome needed. Here are the 3 techniques –
- Gene Inhibition Therapy – this treatment is performed when a dysfunctional gene activity causes an infectious disease or cancer or an inherited disease. The gene introduced should dominate the dysfunctional gene or interfere in a way to stop its undesired activity.
- Killing Of Specific Cells – this treatment is used when the disease can be treated by destroying certain types of cells like cancer. The gene is inserted into a diseased cell that causes its death. The inserted gene either releases a toxic substance that causes the cancer cell to die or releases a marker which allows immunity cells of the body to kill the cancer cells. For this to function properly the targeting of cells for gene delivery should be very precise.
- Gene Augmentation Therapy – this treatment works when a gene mutation stops a product being produced such as a protein which has an essential function. The gene added replaces the defective gene and causes the production of the functioning product to resume. It is helpful only it the damage caused is reversible or any significant damage has not yet happened.
Several challenges that need to be addressed to ensure gene therapy comes forward as a mainstream method of treatment. These are –
- Making sure the gene reaches the right cell.
- Delivery of gene to the healthy cell can cause health issues for the patient and prevent any issues in case the gene reaches the wrong cell.
- A cell may interfere with therapy by shutting the genes which show abnormal activity.
- The gene only gets turned on if it reaches the right cell.
- A way to circumvent the immune system which may target the new gene as an unwanted guest.
- Currently used gene carriers do happen to spark immunity responses.
At the moment, gene therapy is very expensive and limited to individual cases for a thorough approach. As the challenges get overcome slowly, so will be its acceptance and mainstream use.