With the advancement of new technology in the last few years, a person would fancy knowing why the docs recommend a particular treatment and how it works. Gene Therapy is one such area of the medical field under constant research every day. A countless number of researchers in the world who love exploring the genes of our body have agreed upon a definition for gene therapy – “Gene Therapy is an experiment that uses genes to treat or prevent disease”, as stated by MedlinePlus, a famous U.S National Library for Medicine.
“How does Gene Therapy work?” would be our next question afloat in our mind after understanding the above definition.
Gene therapy is a large ocean by itself in the field of medicine. For a start, Gene Therapy works with the introduction of the genetic material into the cells that causes abnormalities in the human body. The gene therapy either results in the correction of the gene or turns it into a useful protein during an unwarned mutation.
Let us dig a little deep and make our way into learning about human gene therapy.
Human Gene Therapy
If we consider the cure for Cancer, Heart Disease, AIDS, Haemophilia and Cystic Fibrosis, Gene Therapy occupies the top shelf. The therapeutic process modifies the expression of a gene or brings about a change in the biological properties of the human cells. It is helpful to treat genetic disorders and other infectious diseases. However, we shall discuss in detail the Gene therapy for cancer in the upcoming section.
There are multiple mechanisms on which gene therapy can work:
- Introduction of a new modified gene into our body as a treatment for the disease.
- Immobilizing the gene hampering the functional properties of the cell.
- Replacing a healthy new gene instead of a troubled old one.
Human Gene Therapy baskets a few products that include:
- Viral vectors: Gene therapy products derived from viruses that are genetically modified and injected into the human body that carries these healthy genes into human cells.
- Bacterial vectors: The bacterias causing diseases are modified, thereby immobilizing their ability to spread the disease and thus allowing them to be carried by the human cells.
- Circular DNA: The genetically handled circular or plasmid DNA is again a vehicle for these therapeutic genes to reach the human cell.
- Human Gene: The human gene can also be a cause for the cure of its disease. The disrupted gene is removed from the human cell, genetically engineered and injected back into the cell(subjected to the usage of Viral Vectors). Thus letting the human cell recognise the right type of gene that needs acceptance.
Gene Therapy for Cancer
According to the recent global survey by Globocan, the death toll due to cancer has risen to over 10 Million (as of December 2020). On the contrary, it also sheds a light on the astounding improvements in the Survival Rates of cancer patients which has also risen from 55% to 76% in the last two years. The positive surge in the survival rates is mostly because of Gene Therapy.
The promising innovative treatment has never failed to save countless lives and bring an optimistic change to their painful lives. However, there are a few concerns advised by the doctors that have to be kept in mind.
The treatment for Cancer through Gene Therapy follows three key approaches:
- Immunotherapy: A therapeutical approach to improvise the immune system of a cancer patient with the use of Viral vectors and genetically modified cells that kill the cancer cells in the process are the principle of Immunotherapy.
- Oncolytic virotherapy: In this approach, the viral particles injected inside the human cell replicate themselves within the cancer cells and destroys them before they could reach the final stages.
- Gene transfer: A new genetically modified gene is inserted into the cancer cell or the surrounding cells that eventually become a killer of the cancer cell, thus preventing further damage.
The treatments have offered a minimum of five-year survival rates even in the worst cases.
CRISPR Gene Therapy
Diving into a bit more detail of the Cancer treatment of Gene Therapy, we have something called CRISPR Gene Therapy. It mainly focuses on editing the gene in the cancer cell. In short, CRISPR is a gene-editing tool that is highly precise and a base for the revolution of cancer treatment in the world.
But how does it work in Gene Therapy?
CRISPR acts like a memory and remembers the vulnerable virus causing cancer. The bacteria used in CRISPR produces the fragments of RNA from its array and attacks the DNA of the foreign virus. There is then the secretion of the enzyme such as Cas9 that slice the foreign DNA thus leaving it deactivated. At this stage, the virus is unable to spread thus preventing the other cells from getting infected.
Scientists and doctors have used this kind of Gene Therapy to cure the genetic blindness disorder. This tiny rework in the DNA structure during eye surgery have borne a positive result. Needless to say, it has a beneficial impact even on the tiniest of mutations. Hence has been used to treat lymphoma and sickle disease apart from the target cancer and genetic blindness.
How is Gene Therapy different from Stem cell therapy?
The Gene and Stem cell therapy more or less sail on the same boat. They dig out the foreign target and replace them with proteins or cells, which leads to suppression of that particular character.
However, both have their differences.
Gene Therapy uses its vectors to transfer their gene into the cell whereas stem cell therapy involves the replacement of a troubled cell.
There are a few instances where Gene Therapy and Stem cell therapy coexist. In such cases, the disrupted cells are removed, genetically modified to express a particular gene and then inject back into the body of the patient. Genetic diseases such as ADA-SCID are treated by this combination.
Pros and Cons of Gene Therapy
Instead of formally learning about Gene Therapy’s pros and cons in points, let us take a different approach here. We shall address the issue in the form of FAQs.
Just like with robotic surgery , Gene Therapy has its definitive advantages and challenging disadvantages that need to be overcome to win the trust of people across the world. Though technologically advanced and relatively quick in expressing the results there are a few common questions pondering the minds of masses, especially patients.
- “Why do we need Gene Therapy?”
Pros: Gene Therapy addresses the solution to the impossible such as a change in the structure of the DNA. Several diseases can be cured with the help of DNA alteration. Different methodologies and new developments have proven their worth with time and the achievement of desired results.
Cons: When there are advantages we also have clinical disadvantages which answers the question “Why don’t we need Gene Therapy?” In a few cases, the virus vectors used for the treatment of cancer can prove their disadvantage when they begin affecting more number of cells than they are intended to. This might pose a potential risk to patients who are elderly or have a weak immune system. Deep learning is recommended to prevent the wrong strand of DNA to be cut or replaced.
- “Is Genetic Therapy a one-time treatment?”
Pros: Improving health condition is the main goal of Gene Therapy. A recovery rate of more than 50% has been recorded for the last 3 years in the case of a bone marrow transplant. It is a beneficial one-time treatment for the children since they are cured of their disorders during their younger stages itself.
Cons: Though a one – time treatment, there are medical proofs where the patients have been treated more than ones owing to their age factor and immunity. Gene Therapy adds to the expensive list of treatments that require deeper pockets. There are only a choosy number of diseases that are cured by Gene Therapy.
- “Can Gene Editing cure diseases?”
Pros: One of the positive points of Gene Editing is, though relatively new, it has a high possibility of curing the disease. Extending the life span by a minimum of 2-3 years in the worst-case proves the quality of the Gene Editing if operated correctly.
Cons: As we have discussed earlier, Gene Editing requires an alteration in DNA or any other mechanisms dealing directly with the DNA. Hence, experienced hands are a top priority. In rare cases, it may lead to introducing new diseases at the cost of curing the old ones.
- “Is Gene Therapy legal?”
Gene Therapy is legalised only in certain sectors and after a lot of clinical trials. A few Governments around the world have legalised it over a limited number of Gene Therapy vectors.
Pros: Let us consider the case where Gene Therapy is legal. It helps us cure diseases like HIV, AIDS, Cancer. Apart from humans, Gene Therapy in plant and animal products helps in getting rid of the diseases and hence surges the economic growth of the country.
Cons: Ethical issues are a part of the legalization of Gene Therapy. Since gene therapy involves making changes within the DNA, which modifies the functionality of the body, many controversies have come up. Most of them concern the natural imbalance of living things that are Genetically modified.
Future of Gene Therapy
The efficiency and success rates of gene therapy have made us wonder where Gene Therapy would be the future of medicine. It is seen and a cure for genetic disorders in children or even before their birth ( during the embryonic stages ). A quick solution for a disease seeking a cure is somehow becoming the tagline for Gene Therapy. With an increased number of clinical tests and extended researches, gene therapy is all set to become the medicine of tomorrow.
For the record gene therapy is not only limited to humans and their disorders, plants and animals also undergo these procedures for productivity and disease-free living.
Acute monitoring of the diseases will be leading to a revolution in business in the medical field. At present, there is already a growth in sponsored industry trails and trails concerning a particular area or a disease, ergo leaves us in no doubt that Gene therapy will make its place soon.
Keeping in mind the pros and cons, the cost and risks of gene therapy and gene-editing technology, many countries have already advanced towards positive health aftermath. Seeking experiences’ guidance and a considerable amount of doctor-practice dealing with genes and foreseeing their results would help gain positive ethical responses.