Technical and Ethical Issues around Gene Therapy, Stem Cell Therapy and Synthetic Biology
Gene therapy is a technique in which genes are inserted into an individual’s cells and tissues to treat or prevent disease. In this technique, the defective mutant allele is replaced with a functional one. The advantage of this technique is that it allows the doctors to treat a disorder by inserting a gene rather than using drugs or performing a surgery. Although the technique is still in its infancy, it looks promising to treat diseases like inherited disorders, cancer and some types of viral infections.
Stem Cell Therapy
Stem cell therapy is a technique that uses the stem cells to treat various disorders ranging from non-serious to life threatening diseases. Stem cells are derived from either cord blood or bone marrow. Bone marrow transplant is the most popular stem cell therapy. Scientists are exploring ways to apply stem cell therapy for neurodegenerative diseases and other conditions.
Synthetic biology is an interdisciplinary branch that combines science and engineering. It helps in the design and construction of novel biological parts, devices and systems as well as helps in the redesigning of natural biological systems for useful purposes. Examples are construction of tumour seeking bacteria to treat cancer and redesign of photosynthetic systems to produce more energy.
Day-to-day applications of these techniques
Gene therapy, stem cell therapy and synthetic biology have several day-to-day applications. In some cases, usage of these techniques has been revolutionary. For example, usage of gene drive technology can wipe out insects and pests. It has been found that the propagation of a genetic modification can hamper sexual reproduction in mosquitoes and will eventually eliminate them. This will help in the eradication of diseases such as malaria, dengue, Zika, chikungunya, yellow fever, among others. In addition, these techniques can also help to eradicate pests that infect crops in agriculture.
Although the above techniques look promising for treating a number of diseases and have several day-to-day applications, they are not free from technical, ethical, and environmental issues. These techniques have not found to be fully safe and effective.
The technical challenge facing these new techniques is the emergence of resistance over a period of time to the nuclease. For example, usage of gene drive technology has in fact imposed a huge selection pressure for resistance development in the pests. Experiments have revealed the emergence of nuclease-resistant mutants.
In case of gene therapy, the techniques itself remains risky and is at present used to treat only those diseases that have no other cures.
Ecologists and environmentalists have expressed the following concerns in using these techniques:
- Breakdown of species barriers,
- emergence of new disease-transmitting vectors, and
- ecological and environmental damages. For example, the consequences of elimination of an insect species.
Stem cell therapy has run into controversy following the ability of the scientists to isolate and culture embryonic stem cells. The controversy primarily revolves around the usage of human embryonic stem cells, which often results in the destruction of the blastocyst. Similarly, the synthetic biotechnology has also got tangled in ethical and bio-security issues. The usage of genetically modified organism (GMO) has triggered debates all over the world. For example, in India, Bt Brinjal is considered as an environmental risk. Also, synthetic biology has triggered ethical questions as it places patents on living organisms. In addition, regulations placed on bioengineering of human embryos have created controversies in the field of bioethics. Critics around the world have been calling for an outright ban on the use of synthetic biology on the human genome.
Suggested Question for GS Mains:
Explain “Gene Therapy”, “Stem Cell Therapy” and “Synthetic biology.” What are key technical, ethical, and environmental issues related to them?