We read the four commentaries on our article with much interest.1 Each response provides stimulating discussion, and below we have attempted to respond to specific issues that they have raised. We regret that we are not able to respond point-by-point to each of them. However, before our responses, it may benefit the reader if we briefly summarise the claims in our article. First, we hold two presuppositions: (1) xenotransplantation research will inevitably continue for the foreseeable future, and (2) causing suffering and pain requires sufficient justification and should be mitigated where possible. Second, based on these two presuppositions, we posit an argument for the further genetic modification of pigs for xenotransplantation that would eliminate certain experiences of pain and suffering should it become possible to do so.

Gibson,2 in his commentary, is sceptical—for good reason—that ‘xenotransplantation-motivated disenhancement would be a temporary stopgap until the organ and tissue shortage problem is solved via less contentious means’. Gibson’s argument is grounded in the fact that the biotechnology industry—of which xenotransplantation is part of—is beholden to economic and market forces that would likely perpetuate constancy, thereby making it difficult to transition away from using disenhanced genetically engineered pigs for xenotransplantation. This point is well taken, …