Is there a moral difference between somatic and germline gene therapies?

By: Dryden Chadwick

The field of gene therapy seeks to treat diseases by transferring engineered genetic material into a patient’s cells.1 This unique approach may provide treatment for various diseases that cannot be managed using conventional drugs, however it pois surely a controversial technique. Somatic gene therapies entail manipulating the genetic makeup of a patient’s non-reproductive cells to treat a disease caused by a genetic mutation, affecting only the patient being treated and leaves reproductive cells unaltered.2 Germline gene therapies, on the other hand, involve manipulation of the genome of a human embryo.2 As a result, the ethical implications of germline gene therapies are more significant in comparison to somatic therapies due to greater safety concerns and issues concerning future generations and their autonomy. 


Safety concerns are often at the forefront of ethical discussions concerning gene therapies and gene editing. Intended changes to the genetic composition of a patient’s cells may inadvertently produce adverse consequences that may do more harm to the patient’s quality of life than good. This may occur by the introduction of something disadvantageous, such as a gene that results in cancer or other pathologies, or by the removal of something advantageous, such as the loss of a gene necessary for the resistance to a virus. When assessing safety risks, it is important to determine who is at risk of harm. Somatic interventions involve manipulation of an individual’s non-reproductive cells to treat a genetic disease, therefore any changes are limited to only affect that individual. Conversely, the reproductive implications of germline gene therapies result in safety concerns posing a threat to the patient directly undergoing treatment, as well as their descendants. Due to the level of manipulation of germline gene therapies, alterations to the genetic composition of germ cells may result in irreversible changes to the germline, affecting an infinite number of individuals in the future.3 The intended changes may also have unforeseen harmful effects, as increasing the frequency of the altered genes may be beneficial to the current generation, but may end up being harmful to future generations. Germline gene manipulation may also harm the embryo itself, as the fetus’ development may potentially be affected. Unintentional changes may result in the manifestation of genetic disorders if the embryo is brought to 
term.3 The significance of the physical and moral harm inflicted on the embryo is controversial and the potential harm to future persons provides a more sufficient basis for the moral objection to germline gene therapies. 


It has been argued that if practical and safety concerns can be sufficiently addressed, these interventions may be permissible if informed consent is provided to those who are affected. Somatic interventions admit sufficient informed consent for the patient undergoing treatment who can be informed of the potential risks. Germline gene therapies however pose the ethical dilemma of lack of consent from future generations. By altering the germline, it may be argued whether current individuals have the authority to make decisions regarding changes to the germline on behalf of future generations. Those who argue for the use of germline gene therapies often present that there are various decisions made that will affect unborn people. Parents make decisions on behalf of their children, thus affecting the next generation, and our current use of resources affects far-away generations due to consequences of climate change. Alterations to the germline may however undermine the autonomy of these unborn people and introduce potential concerns about social justice. Inability to obtain informed consent results in a lack of respect for the autonomy of the unborn persons in question. The moral significance of a decision to alter a germline compared to those previously mentioned could be attributed to the unique ethical significance of germ cells, as they form the link between generations and offer continuity between the present and the future of humanity. The differing relationships between the two types of gene therapies and their engagement with the concept of informed consent distinguish the significance of the moral content of germline gene manipulation over somatic interventions. 


It might be concluded that somatic interventions may be plausible for the treatment of genetic diseases if safety concerns can be sufficiently addressed and informed consent can be obtained from the patient. Germline gene therapies however seem to fall short in attaining these criteria. The potential irreversible unintended changes to the germline which may inadvertently affect future generations who cannot consent offer greater moral concern for the use of germline gene therapies in the practice of medicine. In most cases, there are alternative means to germline gene therapies to achieve the 
same desired result with fewer safety concerns, such as the possible use of artificial reproductive techniques.3 Unless these alternatives cannot be utilized and germline gene therapies are the only method to avoid a lethal genetic disorder, the use of germline gene therapies in practice does not seem to be justifiable. 




1. Gonçalves, G. A. R., & Paiva, R. de M. A. (2017). Gene therapy: advances, challenges and perspectives. In Einstein (Sao Paulo, Brazil). https://doi.org/10.1590/S1679-45082017RB4024 
2. Scheller, E. L., & Krebsbach, P. H. (2009). Gene therapy: Design and prospects for craniofacial regeneration. In Journal of Dental Research. https://doi.org/10.1177/0022034509337480 
3. Chadwick, R. F.; Schüklenk, U. This is Bioethics: An Introduction [Online]; Wiley-Blackwell: Hoboken, NJ, 2020.