Gene Therapy

Genetic modification is a way of altering the DNA sequence (genes) of an organism and, consequently, altering the manufacture of the proteins associated with these genes on which various cellular functions depend. This genetic modification is applied to all fields of biology and biotechnology and the resulting modified organisms are known as transgenic.

In industry, a clear example of the application of genetic modification is the creation of bacterial or fungal strains that produce recombinant proteins, in which an exogenous gene of the species is introduced to obtain the protein of interest.

In biomedicine, genetic modification is beginning to be applied to patients and is known as gene therapy, which can be:


– In vivo: viral inoculation is direct to the patient’s tissue.


– Ex vivo: requires prior culture of the patient’s cells in vitro, viral co-incubation and selection of the cell clones with the correct modification.


In this case, genetically modified cells are introduced directly to the patient and not the viral vectors.

For both strategies, viral vectors must be multiplied (mainly Lentivirus and Adenoassociated), for which industrial production strategies very similar to viral replication for vaccines are usually followed.



Addition Therapy

The introduction of a new gene or a healthy copy to compensate for a defective gene, whereby gene therapy provides the recovery of at least half of the protein’s functionality or gives the cell a new function.

Substituion Therapy

The prior deletion of the defective gene and the subsequent addition of the correct copy.

Did you know?

Ex-vivo therapy has benefited one of the most complex fields such as oncology. Some successful therapies that require the use of the virus are:


– CAR-T: as a treatment for a type of leukemia in which B lymphocytes (tumor cells) present an antigen on their membrane that cannot be recognized by T lymphocytes (immune system cells responsible for destroying tumor cells). In this case, T lymphocytes are removed from the patient, genetically modified to express a new receptor that recognizes the tumor antigen and reintroduced to the patient so that they can bind to the malignant B lymphocytes and destroy them.


– Oncoviruses: this therapy, despite dealing with viral vectors, has a totally different objective. In this case the viruses are designed to attack the tumor cells, infecting them and collaborating (together with treatments such as chemotherapy and radiotherapy) in their destruction. Oncoviruses are modified to increase their binding affinity to target tumor cells as well as to carry immunostimulatory proteins. Thus, upon infection and consequently cell lysis, molecules that enhance the immune response are secreted into the environment.