A gene is a segment of DNA that is passed down from parents to children and gives traits/characteristics to the offspring. Genes control much of your body’s form and function.
Genes that don’t work properly can cause diseases. To tackle this, Gene therapy replaces a faulty gene or adds a new gene in order to cure disease or improve your body’s ability to fight disease.
What is Gene Therapy?
Gene therapy is an experimental technique that involves the insertion of genes(segment of DNA) into an individual’s cells to treat diseases. The new DNA generally contains a functioning gene to correct the effects of a disease-causing mutation.
This technology is still in its infancy yet it has been used with some success. It is useful in curing hereditary diseases in which a defective mutant allele(Wiki) is replaced with a functional one.
Types of Gene Therapy
There are two different types of gene therapy depending on which types of cells are treated:
- Somatic gene therapy: As the name suggests, it involves the transfer of genes only to somatic cells (any cell other than the reproductive cells). Effects of somatic gene therapy will not be passed on to the patient’s offsprings.
- Germline gene therapy: This involves the transfer of a section of DNA(genes) to cells that produce eggs or sperm. Effects of germinal gene therapy will be passed on to the patient’s offsprings and subsequent generations. If the treatment goes successful, this is a permanent cure for the disease.
This type of therapy is prohibited in many countries due to ethical and technical concerns. Why?
Think about genetically modified humans! If this technique would be legal, we would see some wired races of humans around us. And it will expand class differences, people will be choosing superior hybrid embryo similar to hybrid cotton seeds. Know more about Genetic Engineering.
Gene Therapy Techniques
There are several approaches to gene therapy, including:
- Inactivating a mutated gene that is functioning improperly.
- Replacing a mutated gene (that causes disease) with a healthy copy of the gene.
- Introducing a new gene into the body to help fight a disease.
- Making diseased cells more noticeable to the immune system.
This is just a brief introduction of techniques of gene therapy, read detailed and exciting techniques in our next post.
Gene therapy is still under study to make sure that it will be safe and effective. It is currently being tested under clinical trials only for diseases that have no other cures.
Suggested read: Approaches to Gene therapy in detail
How is DNA transferred?
We are talking about the transfer of genes or DNA into your cells. But a gene can’t easily be inserted directly into your cells. Genes usually have to be delivered using a carrier, called a vector. The vector acts as a vehicle to carry the alien gene into the cells of a patient with a genetic disease.
The most commonly used vectors are viruses because they can recognize certain cells and carry genetic material into the cells’ genes. Researchers remove the original disease-causing genes from the viruses and replace them with the desired genes needed to stop the disease.
Now the vector can be injected directly into a specific tissue in the body, where it is taken up by individual cells. Alternately, a sample of the patient’s cells can be removed and exposed to the vector in a laboratory. The cells containing the vector are then returned to the patient. If the treatment is successful, the new gene delivered by the vector will make a functioning protein and helps in curing disease.
Is Gene Therapy Safe?
Current research is evaluating the safety of gene therapy. It is under study to determine whether it could be used to treat disease or not.
Several studies have already shown that this approach can have very serious health risks, such as toxicity, inflammation, and cancer. This technique is relatively new, some of the risks may be unpredictable. However medical researchers and regulatory agencies are working to assure that this research is as safe as possible.
Risks of Gene Therapy
Unwanted immune response: Your immune system may see the newly introduced vectors as intruders and attack them. This may cause inflammation and in severe cases, organ failure.
Infection caused by the virus: It is possible that once introduced into the body, the viruses may recover their original ability to cause disease.
Targeting wrong cells: Viruses have the ability to affect different types of cells. It is possible that the altered virus may infect additional healthy cells that don’t contain mutated genes. It will damage healthy cells, causing other illness or diseases, such as cancer.
The possibility of Tumor Formation.
The Future of Gene Therapy
Gene therapy holds the unlimited potential to be the next big thing in medicine. It is one of the hottest areas of medical research today.
Gene therapy has the potential to eliminate cancer cells without damaging normal, healthy tissue. It may be a promising treatment option for some genetic diseases including Hemophilia, Leukemia, muscular dystrophy and cystic fibrosis.
This technique is patient specific and requires a case-by-case approach. This may be effective, but may also be very expensive.
Tell us in comments below: Do you support Genetic Modification of Human Embryo? Will you enrol for modification, knowing its risks?