Regulating Human Germline Editing

Veronica Orbecchi

Any organism’s characteristics are determined by their genes. Our genes contain information about features like height, the colour of our eyes, or our susceptibility to diseases. Owing to formidable scientific advances, gene editing tools now make it possible to make precise alterations to an organism’s genes in vivo. Among the promising applications of gene editing, these tools may help prevent or treat various diseases, increase the efficiency of agriculture and food production or significantly improve research methods. Since the discovery of CRISPR-Cas9 one decade ago, gene editing has become much faster, cheaper and more reliable than previous strategies that were being developed since the 1980s (Baylis et al, 2020). While the remarkable potential of gene editing to bring about positive change increases with its ever growing effectiveness, this potential is undeniably accompanied by a number of un-negligible risks and a certain degree of moral unease. This elicits the need for appropriate regulations for these techniques.

What can CRISPR-Cas9 do?

Since CRISPR-Cas9 has a wide range of distinct applications, appropriate public policy should deal with them accordingly. For instance, different regulations are in place for gene editing in human medicine, agriculture or research. In the case of human medicine, a distinction is often made between somatic and germline gene editing (e.g. Bergman, 2019). Somatic gene editing involves modifying a patient’s DNA in any cell other than sperm and egg cells, which implies that genetic changes only apply to the treated individual and are not inheritable by their offspring (ibid). This may allow to treat particular diseases caused by genetic mutations that affect a single organ or tissue. For example, certain blood pathologies may be treated by using CRISPR to modify blood stem cells such that, when infused back into the patient, they generate healthy blood cells that compensate for deficiencies (Quintana-Bustmante e al, 2022). Currently, clinical trials are also being conducted to devise such treatments for certain untreatable cancers. Germline gene editing, on the other hand, involves modifications of an embryo at its early stages, which would affect every cell of the future organism (Bergman, 2019). These modifications would thereby be inheritable by descendants, and passed on to future generations. Consequently, the therapeutic appeal of germline gene editing is that it would, for example, help eradicate certain genetic diseases caused by inheritable mutations. Indeed, by modifying the germline cells of individuals who carry certain mutations, it would be possible for them to have babies without risking to pass on potentially dangerous diseases (ibid).

Current policy landscape for germline editing

 Despite the numerous potential healthcare benefits of gene editing, it is important that public policy takes into account the practical and moral drawbacks of these tools in order to appropriately regulate the use of CRISPR-Cas9. Compared to policies for somatic gene editing, regulations on germline editing are far more restrictive. A comprehensive survey of 96 countries found that none explicitly permitted germline editing on embryos meant for reproduction, and that 70 out of 75 countries with relevant policy documents explicitly prohibited germline editing, with 5 countries allowing minor exceptions (Baylis et al, 2020) (Figure 1). However, several countries permit gene editing on embryos purely for research purposes, where embryos will not be successively used for pregnancy (ibid) (Figure 2). Beyond outright prohibition, other regulatory approaches that significantly affect the development and use of gene editing technologies include the extent to which research on these practices is funded.

Considerations relevant to human germline editing policy

The tendency for restrictive policies towards germline editing reflect a cautious approach that is being taken because of a variety of ethical and practical concerns related to gene editing. In this regard, in a 2018 report, the Nuffield Council on Bioethics highlights the value of procreative freedom, emphasising the value of germline gene editing to allow healthy procreation from carriers of genetic diseases. Still, two ethical principles are highlighted: safety and social justice (Nuffield Council on Bioethics, 2018).

1. Safety: One important question for public policy is how to deal with uncertainty and risk. While CRISPR-Cas9 is undeniably more precise and safe compared to previous gene editing technologies, many still do not deem it sufficiently precise to be used on human embryos for reproduction. For instance, off-target effects are possible. These are unintended alterations in locations of the genome other than the targeted mutation. Since these off-target alterations may lead to unknown irreversible effects on the edited embryos, it is argued that germline gene editing would create unacceptable risks for the unborn individual (Schleidgen et al, 2020). For example, in the USA, the National Institutes of Health (NIH) made the decision to not provide funding for human gene editing technologies on the basis that the concept of human germline editing raises “serious and unquantifiable safety issues” (NIH, 2015). Still, although the potential risks of CRISPR may warrant a restrictive regulatory approach with regards to the actual utilisation of this tool for germline editing, the issue of safety also speaks in favour for the encouragement of research on embryos that will not be used for reproduction. Current bans of germline editing for reproduction would thereby be seen as temporary prohibitions until the practice is deemed sufficiently safe. Moreover, in order for safety to be a viable argument in favour of prohibition, it must also be the case that the risks involved in making genetic alterations to embryos to prevent genetic diseases are greater than the risks of the genetic diseases themselves (Schleidgen et al, 2020).

2. Social inequality: Even if germline gene therapy were considered fully safe to use, proper regulation would have to ensure that there is equitable access to it, in order to avoid exacerbating social inequality. Indeed, inequitable access to gene editing might lead to a situation where only the wealthy are able to prevent certain genetic disorders. This Again, rather than justifying permanent prohibition, this concern elicits the need for policies which attempt to circumvent issues of social inequality.

3. Other considerations: Other common considerations include worries about germline editing on healthy embryos for non-therapeutic purposes— purely to select particular features. While some believe that germline gene therapy may only be morally acceptable for therapeutic purposes, the distinction between therapy and enhancement is arbitrary and difficult to discern. Moreover, certain religious groups seek to protect the moral status of an embryo, leading to restrictive approaches to research on germline editing (NIH, 2017). Due to the controversial nature of the issue of human germline editing, it is important that public policy simultaneously appreciate the potential social benefits of these techniques while remaining mindful of their risks and ethical permissibility.


Baylis, F., Darnovsky, M., Hasson, K. & Krahn, T. (2020). ‘Human Germline and Heritable Genome Editing: The Global Policy Landscape.’ The CRISPR Journal, 3(5), 365-377.

Bergman, M. T. (2019). ‘Perspectives on gene editing.’ story/2019/01/perspectives-on-gene-editing/. Accessed 20 Nov 2022.

European Parliamentary Research Service. (2022). ‘Genome Editing in Humans: A Survey of Law, Regulation, and Governance Principles.’ etudes/STUD/2022/729506/EPRS_STU(2022)729506_EN.pdf. Accessed 20 Nov 2022.

National Institutes of Health. (2015). ‘Statement on NIH funding of research using gene[1]editing technologies in human embryos.’ Accessed 20 Nov 2022.

National Institutes of Health. (2017). ‘What are the Ethical Concerns of Genome Editing?’ Accessed 20 Nov 2022.

Nuffield Council on Bioethics (2018) Genome editing and human reproduction: social and ethical issues. Accessed 20 Nov 2022.

Quintana-Bustamante, O., Fananas-Baquero, S., Dessy-Rodriguez, M., Ojeda-Perez, I. & Segovia, J. C. (2022). ‘Gene Editing for Inherited Red Blood Cell Diseases.’ Frontiers in Physiology, 13.

Schleidgen, S., Dederer, H. G., Sgodda, S. et al. (2020). ‘Human germline editing in the era of CRISPR-Cas: risk and uncertainty, inter-generational responsibility, therapeutic legitimacy.’ BMC Medical Ethics, 21(87).

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