Gene therapy is an
experimental technique that harnesses genes to treat or prevent disease, via
the insertion of genetic material into cells to compensate for abnormal genes
or to produce a beneficial protein. To enable a gene inserted directly into a
cell to function, a genetically engineered carrier, known as a “vector,” is
often required to deliver the gene to its destination. Some viruses can be used
as vectors, carrying the new gene by infecting the cell. When used in humans,
these viruses are modified so as to prevent them from causing disease.
Gene therapy is still in the
experimental stage and involves significant risks, including an undesirable
response by the immune system; insertion of the active gene into the wrong
cells, which could harm healthy cells and result in cancer or tumor formation;
and infection by the carrier virus, which could regain its original pathogenic
qualities. In the past, this therapy has even led to patient deaths. It therefore
remains a residual treatment, to be attempted only after all other
therapy options have been exhausted, that is, in patients without any other
effective therapeutic alternative. In the future, this technique might enable
doctors to treat genetic disorders by inserting a gene into the patient’s cells
by means of medication or a surgical procedure.
There are currently several
experimental approaches to gene therapy:
- Replacing
a mutated gene that
is causing disease (by failing to produce a vital protein or producing an abnormal
one) with a healthy copy of that gene (to restore the protein’s activity).
- “Deactivating”
a mutated gene that
is not functioning properly.
- Introducing
a new gene into
the body to assist in treating or fighting off a disease.
Selected ethical issues:
- Experimental treatment involving not insignificant risks – i.e.,
a problematic risk : benefit ratio.
- Adequate informed
consent – awareness of the therapy’s risks.
- Achieving genetic change by introducing genes to reproductive
cells (germline gene therapy), leading to future generations inheriting
the change – human control over the creation of humans (“playing God”).
- Costly treatment raises issues of (un)equal access and
distributive (in)justice
- Elective use of therapy (“off label” use, contrary to medical
intent) to enhance human traits such as height, intelligence, and so on.
Sources:
https://ghr.nlm.nih.gov/primer/therapy/genetherapy
https://ghr.nlm.nih.gov/primer/therapy/procedures
https://ghr.nlm.nih.gov/primer/therapy/ethics
https://www.mayoclinic.org/tests-procedures/gene-therapy/details/risks/cmc-20243698