- How it is done
- CRISPR Technique
- Car T-Cell Technique
- Diseases that gene therapy can treat
- Gene therapy against cancer
Gene therapy, also known as gene therapy or gene editing, is an innovative treatment that consists of a set of techniques that can be useful in the treatment and prevention of complex diseases, such as genetic diseases and cancer, by modifying specific genes.
Genes can be defined as the fundamental unit of heredity and are made up of a specific sequence of nucleic acids, that is, DNA and RNA, and which carry information related to the person's characteristics and health. Thus, this type of treatment consists of causing changes in the DNA of the cells affected by the disease and activating the body's defenses in order to recognize the damaged tissue and promote its elimination.
The diseases that can be treated in this way are those that involve some alteration in the DNA, such as cancer, autoimmune diseases, diabetes, cystic fibrosis, among other degenerative or genetic diseases, however, in many cases they are still in the development phase. tests.
How it is done
Gene therapy consists of using genes instead of drugs to treat diseases. It is done by changing the genetic material of the tissue compromised by the disease by another that is normal. Currently, gene therapy has been performed using two molecular techniques, the CRISPR technique and the Car T-Cell technique:
CRISPR Technique
The CRISPR technique consists of altering specific regions of DNA that could be related to diseases. Thus, this technique allows genes to be altered in specific locations, in a precise, fast and less expensive way. In general, the technique can be performed in a few steps:
- Specific genes, which can also be called target genes or sequences, are identified; After identification, scientists create a “guide RNA” sequence that complements the target region; This RNA is placed in the cell along with the Cas 9 protein, that works by cutting the target DNA sequence; then a new DNA sequence is inserted into the previous sequence.
Most genetic changes involve genes located in somatic cells, that is, cells that contain genetic material that is not passed on from generation to generation, limiting the change to just that person. However, research and experiments have emerged in which the CRISPR technique is performed on germ cells, that is, on the egg or sperm, which has generated a series of questions about the application of the technique and its safety in the development of the person..
The long-term consequences of the technique and gene editing are not yet known. Scientists believe that the manipulation of human genes can make a person more susceptible to the occurrence of spontaneous mutations, which can lead to overactivation of the immune system or the emergence of more serious diseases.
In addition to the discussion about the editing of genes to revolve around the possibility of spontaneous mutations and transmissibility of the alteration for future generations, the ethical issue of the procedure has also been widely discussed, since this technique can also be used to alter the baby's characteristics, such as eye color, height, hair color, etc.
Car T-Cell Technique
The Car T-Cell technique is already used in the United States, Europe, China and Japan and was recently used in Brazil to treat lymphoma. This technique consists of altering the immune system so that tumor cells are easily recognized and eliminated from the body.
For this, the defense T cells of the person are removed and their genetic material is manipulated by adding the CAR gene to the cells, which is known as a chimeric antigen receptor. After adding the gene, the number of cells is increased and from the moment that an adequate number of cells is verified and the presence of more adapted structures for tumor recognition, there is an induction of worsening of the person's immune system and, then, injection of defense cells modified with the CAR gene.
Thus, there is activation of the immune system, which starts to recognize tumor cells more easily and is able to eliminate these cells more effectively.
Diseases that gene therapy can treat
Gene therapy is promising for the treatment of any genetic disease, however, only for some can already be performed or is in the testing phase. Genetic editing has been studied with the aim of treating genetic diseases, such as cystic fibrosis, congenital blindness, hemophilia and sickle cell anemia, for example, but it has also been considered as a technique that can promote the prevention of more serious and complex diseases, such as for example cancer, heart disease and HIV infection, for example.
Despite being more studied for the treatment and prevention of diseases, the editing of genes can also be applied in plants, so that they become more tolerant to climate change and more resistant to parasites and pesticides, and in foods with the objective of being more nutritious.
Gene therapy against cancer
Gene therapy for cancer treatment is already carried out in some countries and is particularly indicated for specific cases of leukemias, lymphomas, melanomas or sarcomas, for example. This type of therapy consists mainly of activating the body's defense cells to recognize tumor cells and eliminate them, which is done by injecting genetically modified tissues or viruses into the patient's body.
It is believed that, in the future, gene therapy will become more efficient and replace current treatments for cancer, however, as it is still expensive and requires advanced technology, it is preferably indicated in cases that do not respond to treatment with chemotherapy, radiotherapy and surgery.
