Research Stream: Social Technologies
Author: Sharon Adedapo, Research Assistant, PatentsInHumans Project, ALL Institute and Department of Law and Criminology
In September 2024, the European Patent Office (EPO) denied the University of Minnesota’s patent application (EPO decision T 1553/22) for developing human-animal chimeras by putting human stem cells into animal embryos, such as pigs. It would empower pigs with the ability to produce human stem cells and blood vessels, thus facilitating the harvest of organs that are compatible with humans. The main goal was to address the severe lack of suitable donor organs, and in turn, lessening the long waiting lists seen worldwide. While this case focused on the patentability of the technology, it raises broader debates about the ethical boundaries of human-animal chimera research and morality.

The EPO cited ethical concerns under Article 53(a) of the European Patent Convention (EPC). Article 53(a) expressly prohibits patents that violate “ordre public or morality”. Put simply, ‘ordre public’ refers to the protection of the environment, public safety, and individuals. ‘Morality’ pertains to behaviours that are deemed to be right or acceptable according to deeply ingrained European cultural values. Article 53(a) is complemented with the EU Biotechnology Directive which explicitly states that “processes, the use of which offend against human dignity, such as processes to produce chimeras from germ cells or totipotent cells of humans and animals, are obviously also excluded from patentability”. It is important to note that these provisions address concerns related to the commercial exploitation of morally contentious technologies, not specifically their scientific use. The EPO’s remit is limited to patent law and does not regulate the use of the technology.
In Greek mythology, a ‘chimera’ was a fire-breathing hybrid mythical creature with the head of a lion, the body of a goat, and the tail of a serpent. Today, the term has taken a completely different meaning in science. In simple terms, a ‘chimera’ is now used to describe an organism composed of cells from two or more genetically distinct entities. Human-animal chimeras have been widely used in research to study neurodegenerative diseases, genetic disorders, and cancer treatments, and to grow transplantable organs. There is considerable research or interest around the potential for the use of human-animal chimeras for organ transplant in the future. However, significant ethical and moral considerations and scientific challenges arise in this context. The primary question, being: Where should the line be drawn between scientific progress and moral/ethical responsibility?
The field of biotechnology combines biology with technology to develop innovative solutions that improve human health and sustain the environment. It has transformed sectors such as healthcare, agriculture, and diagnostics, playing a vital role in the development of new medications, life-saving vaccines, and advanced medical tools. One emerging application is the development of human-animal chimeras. Scientists have introduced human stem cells into animal embryos, such as pigs, with the aim of growing organs compatible with humans for transplantation. This process, which uses techniques, such as genetic engineering and stem cell manipulation, is driven by the urgent need to address the global shortage of donor organs.. Thousands die each year while waiting for organ transplants, and chimeras may offer a promising solution by producing organs less likely to be rejected by the recipient’s immune system. Despite the potential, the science remains complex and uncertain, with many questions around feasibility and long-term outcomes. Moreover, the development or use of human-animal are not currently permitted in many jurisdictions due to ethical and legal concerns.
Despite the potential medical benefits of human-animal chimeras, they raise significant ethical concerns such as; cognitive enhancement and human-like consciousness, the development of human physical traits in animals, the production of human gametes in animals, the risk of new diseases, and moral and species boundaries. A key concern for the EPO in the 2024 case was the possibility of human cells integrating into an animal’s brain or reproductive system, leading to unforeseen consequences. The EPO’s Board of Appeal (BOA) held that patenting such technology may violate human dignity if they make a substantial contribution to a chimera’s cognitive development. They found that despite the potential therapeutic and medical benefits of the invention, they could not dismiss ethical concerns relating to the patentability of this type of technology under European patent law. Another major issue is the precedent that such research would set for the monetisation of human biological material. Critics argue that the development of human-compatible organs in animals blurs the line between species, presenting difficult questions regarding control, exploitation, and ownership of partial human life forms. The tension between ethical responsibility and scientific innovation is not a new debate in the field of biotechnology. Past cases, such as the Oncomouse/Harvard University case (T 19/90) illustrate the EPO’s attempt to strike a balance between medical benefits and ethical issues.
Ethical objections to human-pig chimeras remain strong, particularly because of the concern regarding cognitive humanisation and the potential for the development of ethically significant features. To prevent chimeric organisms from developing consciousness or self-awareness, many bioethicists support strict safeguards, such as ensuring that human cells do not fuse into brain tissue. Many researchers and scientists argue that scientific research should be conducted with caution until we can conclusively determine the moral status of chimeras. Others suggest that the speculative ethical concerns are outweighed by the life-saving potential of these advancements. However, without clear and explicit safeguards, the scientific community seems to still be unsure as to how much chimera research should be conducted.
Just as the ALL Institute is committed to interdisciplinary research that enhances the lived experiences of individuals, the research on chimeras calls us to consider not only medical advancements but also the social and moral implications of these breakthroughs. At the heart of the ALL Institute’s approach is a commitment to people-centered care that addresses clinical, emotional, and social needs, which is particularly relevant when we look at chimeric research. Can chimeric research strike a balance between the pursuit of medical progress and the protection of human values, ensuring that innovation in one area does not unintentionally harm others?