We explain the basics of this cutting-edge medical technology.
Genes largely determine the functions of our body. Our genetic material, in the form of DNA, serves as an instruction book for our cells to know exactly what to do at different stages of our life and development. The importance of DNA in bodily functions makes it a very interesting therapeutic target.
For this reason, doctors and scientists have spent many years trying to act directly on the genetic material to cure diseases and benefit our health. This practice is called gene therapy, and in this article we will explain what it consists of and possible uses that can be given to it.
- If you want to catch up on genetics and enjoy this article more, we recommend that you first read: “https://healthymortel.com/differences-between-dna-and-rna/”
What is Gene Therapy?
In the 1954 science fiction classic “I am Legend” by Richard Matheson, which received a 2007 remake starring Will Smith, society collapses after an apocalyptic epidemic that turns human beings into something like vampires. or zombie.
This collapse is due to the use of a genetically modified virus to cure cancer and is an example of gene therapy used in the literature , long before its practical application in modern medicine. Fortunately, the side effects of gene therapy are not as catastrophic as those in Matheson’s novel.
Gene therapy consists, speaking in general terms, in managing to change the way our DNA works , either because it is not working correctly or because we want to produce another therapeutic effect in the organism.
This can be done in various ways, some of which we will explain below, and its therapeutic effects will vary depending on the type of therapy that is performed, in addition to the instructions that we are modifying in the patient’s genetic material.
- It might interest you: “Achondroplasia: what it is, causes, symptoms and possible treatments”
Are there real examples?
A clear real example of gene therapy occurred in 1990, when W. French Anderson and his team introduced genetically modified immune cells into the body of a four-year-old girl who suffered from a rare immune disease called “severe combined immunodeficiency due to adenosine deaminase deficiency”. ”, also known as ADA. Currently this patient is healthy and does not present any health problems.
ADA disease was perfect to try to cure it by gene therapy , since it is caused by a genetic deficiency. People with ADA do not have working copies of a gene on chromosome 20 important for immune system function, so introducing immune cells that do carry this gene into the patient’s body can prevent the disease.
This type of gene therapy uses the patient’s own cells, which, once extracted and genetically modified, are reintroduced into the patient to carry out the therapeutic effect. In the example above, this therapeutic effect was the introduction of the healthy gene into the population of immune cells so that the patient would have a normal life without immunodeficiencies .
several different types
Depending on how changes are introduced to the patient’s genome, as well as depending on what changes we are going to make, there are currently several different types of gene therapies under investigation and use . Below we discuss some of the less complex ones.
1. Introduction of modified viruses
Viruses are ideal vectors for gene therapy. This is because viruses have two components, an envelope that allows them to be transported and genetic material that is introduced into the cells they infect.
In viral gene therapy, the genetic material of different types of viruses (such as adenoviruses, retroviruses or adeno-associated viruses) is modified so that they contain DNA that is of interest to introduce into the cells of patients. This is the most widely used type of gene therapy today, due to its lower cost and good results .
2. Introduction of modified cells from the patient
This method is the one exemplified in the previous section of the article. It consists of extracting cells from the patient, which are modified by introducing the necessary genomic changes . After modification, they are reintroduced into the patient. This is used medically in some immunotherapy techniques, with applications for example in the field of cancer.
The potential of this technique is very broad, especially if we take into account the existence of stem cells, and it is also known as cell therapy.
3. Introduction of other particles
It is not just cells or viruses that are introduced into patients. DNA can be introduced directly into the cells of patients , although it is less effective than other methods. This drop in effectiveness is due in part to our body’s systems that eliminate foreign DNA (necessary defense against viruses).
The effect of introducing DNA directly into the patient’s cells is of much shorter duration than other methods, in which the DNA manages to enter the patient’s nuclear DNA, since inside the nucleus it is protected from the effects of degradation.
Currently, applications are also being considered in which gene therapy is complemented by the use of nanotechnological techniques, to improve the degree of efficiency of the process and to be able to act on very localized tissues, such as tumors.
Conclusions about this technology
Gene therapy is more than a technique used punctually for genetic disorders. Technologies like CRISPR-Cas used in tandem with gene therapy or different types of cell therapies are only small beginnings in a field of medicine that is now sprouting and growing at an astonishing rate.
Even so, gene therapy has elements that can become worrying if not approached responsibly. The case of the modification of the CCR5 gene in preimplantation embryos that was carried out in China in 2018 is currently famous. This case of gene therapy has brought a lot of controversy, since the germinal lineage of the DNA of the twins, who were born in October, was edited of 2018.
The modification of the germ cells, unlike those carried out on autosomal cells, are modifications that can be transmitted to offspring. Many people are against the modification of the germ cells, since the changes introduced can affect other people in the following generations. This is seen as an affront to human genetic material, which is the heritage of all .
Despite its dangers, gene therapy is here to stay. From outside science, the only thing we can do is inform ourselves and make our opinion heard so that the necessary health and safety standards are respected so that science can evolve causing the least possible harm to human beings.
Bibliographic references
- Keeler, AM, ElMallah, MK, & Flotte, TR (2017). Gene Therapy 2017: Progress and Future Directions. Clinical and translational science, 10(4), 242–248. doi:10.1111/cts.12466.
- Scheller, EL, & Krebsbach, P.H. (2009). Gene therapy: design and prospects for craniofacial regeneration. Journal of dental research, 88(7), 585–596. doi:10.1177/0022034509337480.
- Goncalves, G., & Paiva, R. (2017). Gene therapy: advances, challenges and perspectives. Einstein (Sao Paulo, Brazil), 15(3), 369–375. doi:10.1590/S1679-45082017RB4024.
To the classic question “what do you do?” I always answer “basically I am a psychologist”. In fact, my academic training has revolved around the psychology of development, education and community, a field of study influenced my volunteer activities, as well as my first work experiences in personal services.