Moral Judgments About Genetically Modified Humans (GMHs)

Advances in human gene-editing technologies are outpacing policy and legislation. The development of gene-editing techniques such as CRISPR-Cas9 has simplified the process of gene-editing drastically, enabling scientists to insert, edit and remove sections of DNA more easily than before. The advances in human gene-editing create both hope for the treatment of many diseases and disorders as well as many novel ethical challenges. The ultimate impact of gene-editing technology is contingent on whether and how people are willing to use it. Yet, despite these major leaps forward in gene-editing technology, little research has been devoted to understanding the factors that influence people's moral judgments about human gene-editing.

In the present thesis I employ the psychological literature on attitudes to genetically modified organisms (GMOs) to examine different factors that play a role in people's moral judgments about human gene-editing. Across seven studies, utilizing correlational and experimental methods, I examine moral judgments about human gene-editing. In Chapter 2, Studies 1 (n = 447) and 2 (n = 348) provide preliminary evidence for the role of perceived harm in support for human gene-editing. Specifically, perceived harm was negatively associated with support for human gene-editing, and perceived benefits positively associated with support, while purity concerns and disgust were unrelated to support for these technologies.

I then turn to the effect of gene-editing purpose on judgments about human gene-editing. Three studies were the first to employ a carefully matched experimental design to examine the effect of treatment vs. enhancement purpose of human gene-editing on support. These studies also examined the role of different moral considerations such as the perceived moral rule violation and outcomes in terms of harms and benefits (Ch. 3). In Studies 3 (n = 369) and 4 (n = 394; Ch. 3), participants were significantly more supportive of human gene-editing for treatment purpose (e.g., to improve the physical functioning of people with physical disabilities) compared to for enhancement (e.g., to improve the physical functioning of people without physical disabilities). Further, the lower support afforded to enhancement vs. treatment purpose was mediated by endorsement of both outcome-based and rule-based moral considerations. Specifically, participants viewed enhancement (vs. treatment) as producing less benefits for people and as more of a moral rule violation. These perceptions partially accounted for the lower support afforded to enhancement (vs. treatment). The aim of Study 5 was to test whether the influence of purpose is specific to human gene-editing rather than GMOs more broadly, thus I experimentally manipulated whether the target of gene-editing was people or farm animals in a between-participants design (Ch. 3; n = 355). Study 5 also included a measure of the perception of unfair advantage from gene-editing. Enhancement (vs. treatment) purpose was viewed as more unfair and was afforded less support when the target of gene-editing was people, but not when the target was farm animals. Additionally, unfairness mediated the effect of purpose when the target of gene-editing was people, but not when the target was farm animals. In Chapter 4, the final study sought to replicate the findings across a wider range of domains than just physical functioning. Study 6 (Ch. 4; n = 329). Utilizing a mixed design, Study 6 was the first to show that the lower support for genetic modification for enhancement (vs. treatment) purpose replicates in other domains aside from physical functioning, including longevity, mobility, intelligence and disease resistance. Additionally, the results of Study 6 demonstrated that although participants in general showed a preference for conventional methods over genetic modification, the lower support afforded to enhancement (vs. treatment) was explained by reduced perceptions of social benefit and increased perceived unfairness for both methods. Together the findings suggest that the purpose is central to the level of support afforded to human gene-editing, with enhancement (vs. treatment) consistently receiving less support, even when the function that is targeted is identical (e.g., physical functioning). Further, endorsement of both outcome- and rule-based moral considerations account for the different levels of support afforded to human gene-editing for enhancement (vs. treatment). Importantly, human gene-editing evoke different moral considerations compared to GMOs, for instance regarding fairness concerns, which explain the effect of purpose on support when people are gene-edited, but not when farm animals are. In concert, these findings demonstrate that the purpose, outcome- and rule-based moral considerations all play a role in people's moral judgments about human gene-editing. A final chapter (Ch. 5) discusses implications for the literature on opposition to GMOs, and harm- and rule-based moral considerations in moral judgments. The final chapter also outlines some avenues for future research in moral judgments about human gene-editing and potential significance for regulatory frameworks of human gene-editing.