Drug development is a slow process involving years, even decades, of research and animal models have always been integral to this work. But progress in translating animal work into human benefits has been uncertain.
A recent article published on this site considered this alongside technological advances and asked whether research on animals is now irrelevant. And, if so, why we persist in using them. I will be providing a counter argument to the article, which concludes we should stop using animals in research.
Not a casual choice
First, let’s put to bed the idea that research scientists treat animals as merely a means to an end, or that they are an incidental first choice of research method.
All scientists who work with animals spend a significant proportion of their time applying for approval from their institutional animal ethics committee for their work, and ensuring that approval is maintained. The committee is comprised of vets, experienced researchers, members of animal welfare organisations and independent people who are not associated with animal-based research, or with the institution.
It’s the responsibility of the scientist to meet the requirements of the Australian Code of Practice for the Care and Use of Animals for Scientific Purposes. Failure means the denial of access to animals for research. And under New South Wales legislation, the penalty for cruelty to animals carries an imprisonment sentence of two years or more. Similar rules apply in all Australian states and territories. So, the consequences for deviating from accepted ethical guidelines are well understood and severe.
And it’s cheaper, quicker and easier to first test drugs using computer models and tissue cultures. This is why most researchers make a concerted effort to screen potential drugs in these systems, and only select the best performing ones to test in animal models.
So, ethical issues aside, there’s also a financial drive to minimise animal use.
Researchers are very aware that animals aren’t people. Obviously animal responses aren’t the best possible predictor of treatment effects or side-effects in individual humans. But, what most scientists study are evolutionarily conserved physiological processes, that is, processes that are similar across different species.
Say someone is developing a drug that should act on opioid receptors. The questions researchers ask are – does the drug target what it’s supposed to, and then, does that give rise to a benefit in treating a disease? To this end, mouse opioid receptors work just as well as human ones.
Far from treating animals like small humans, individual animal models and even strains within individual animals are analysed many times over for their suitability to the research being done, and constantly improved until the best possible parallel is found. One strain of mouse, for instance, is very good for replicating a human-like pathology of asthma compared to others that barely develop any signs of respiratory illness. Instead of rejecting all mouse models of asthma as useless, researchers choose the strain that allows them to best approximate the problem.
Genomics and animal models
The revolution in biotechnology over the last two decades has given rise to various disciplines with the suffix “-omics”. They involve the large-scale study of subjects using a variety of molecular, cellular and computational techniques. Proteomics, for example, refers to the study of the entire family of proteins, including their structure and function, in a given organism.
Disciplines such as proteomics give the impression that they spell the end of animal-based research. But what they actually do is provide researchers with the necessary tools to design animal experiments. They enable researchers to look across the genomes of different species, compare the genes and proteins they’re interested in with those in humans, and make informed research decisions.
The other common misconception is around the discipline of genomics, which has led to identifying genes implicated in human diseases. This doesn’t eliminate the need for animals in research. Many genetic mutations actually cause disease (as in the case of this very interesting Pakistani family) or increase the risk of developing one.
What these studies tell us is that a gene is related to a disease (an association) and not necessarily the way it is involved. The use of genetically modified animals lets us study how the gene in question affects the development of an organism from embryo to adulthood, its physiology and behaviour at each of these stages, as well the minutiae of the cellular and molecular processes affected.
This is an incredibly powerful tool for identifying novel targets for therapy. But it doesn’t preclude the use of animals in research.
Lack of suitable alternatives
The list of proposed alternatives to animal research proposed in the article calling for an end to it include prevention programs, epidemiological studies, autopsies, in vitro research in cell cultures and computer modelling.
The first three are not alternatives at all. They don’t actually lead to the development of novel treatments, just a better understanding of the efficacy of existing ones. Meanwhile the last two are already commonly used in most labs, but prior to and in conjunction with work with animals.
And as powerful as modern computers are, there’s still simply no comparison – the idea of successfully simulating the complexity present in organism-level biological systems is a pipe dream at present.
We must be careful not to confuse the effectiveness of animal models with the ethics of using animals for research. People who seek to promote an end to animal-based research claim to have scientific reasons to discontinue it. But this is diversionary, a reframing in much the same way the “scientific controversy” of intelligent design seeks to draw attention away from theological arguments of creationism.
There are many valid and pressing ethical questions that surround the use of living organisms in any capacity, whether in research, farming, for companionship or conservation. These questions constantly drive us toward better practices that minimise animal suffering. But the effectiveness or necessity of animal-based research – regardless of what we think of it – is not in question.