Many animals used in research experience tremendous amounts of pain. Genetic disenhancing could "alleviate" this pain, but the most ethical option is not using animals in the first place.

Countries across the European Union use around 12 million animals in scientific research each year. There are several measures in European law that aim to address the suffering experienced by these animals used: for example, researchers are expected to replace animals with non-animal models wherever possible; reduce the number of animals used to achieve their research goals; and refine their procedures to improve animal welfare. It’s called the 3Rs approach, and furthermore, researchers who use animals must demonstrate in a harm-benefit analysis why the expected benefits of their research justify the expected harm to the animals they use.

Despite these guidelines, millions of animals continue to be used and to suffer in research. Seeing that the number of animals used for research in the E.U. has not changed much over the last decade, and is likely to remain high, the authors of this article propose a way to improve research animal welfare through gene editing.

The authors explain that gene-editing technologies may be able to modify the genes of research animals in a way that makes them incapable of feeling pain or suffering the way they do currently. The idea of such “genetically disenhanced” animals – previously proposed by Adam Shriver for factory farm animals – envisions a world where such animals still pick up on and react to painful stimuli but without the negative subjective experience. Such a phenomenon has been demonstrated in human patients, whose affective dimension of pain have been modified without altering their sensory dimension of pain, resulting in less suffering and less unpleasant feelings.

This article focuses on the pros and cons of such an approach to improving research animal welfare. The related topics of other potential disenhancements (e.g. making non-conscious animals) and the ethics of removing a living being’s innate capabilities have already been discussed in articles other than this one, and other forms of suffering (e.g. removing fear or thirst) are also put to the side.

One potential con that the authors consider is that researchers who work with such disenhanced animals may be more careless when handling them, thus potentially causing greater injury. The authors also consider the objection that creating genetically disenhanced animals goes against the principles of reducing the number of animals in research and replacing animal models with non-animal models. Some people even point out the danger of animal experiments becoming worse and more widespread as a result of having genetically disenhanced animals at their disposal. This concern is especially pressing if using genetically-disenhanced animals makes demonstrating the harm-benefit justification of animal research trivially easy.

However, the authors of this article believe that the potential possibility to improve animal welfare now is worth the potential risks it may bring. The authors also consider the con of such disenhancements altering the validity of test results by introducing a new factor (i.e. lack of pain perception). However, they point out that pain itself (and any corresponding stress) also has effects on the physiology and behavior of animals used in research, and these effects already alter study results.

More research is needed on using gene editing to remove or reduce the subjective perception of pain in lab animals. Additionally, the authors say that more discussion and research is needed to determine whether genetically disenhancing animals would ultimately be a good idea. This article presents a very complicated issue for advocates, one that challenges our very perception of animal welfare. Advocates can continue to stay informed on the latest advancements in the science and ethics of this proposal, but in the meantime, it would be wise to approach the issue skeptically, and keep in mind that the best way to reduce pain in animal research is to not use sentient animals in the first place.

