As students in veterinary and medical school, we were struck by how differently we treated the same diseases in animals and humans. For example, humans were given penicillin for infections but guinea pigs were not.
Some medications that caused birth defects in humans could be given to animals with impunity and vice-versa.
Some cancers that kill Americans every day are harmless in dogs. In light of these and other differences between humans and animals, we began to question how animal experimentation could ever hope to cure human disease.
We became alarmed when we realized that slight differences between animals and humans in anatomy, biochemistry, and physiology made it dangerous and cavalier to apply to humans the results of experiments on animals. The money wasted on animal experimentation dismayed us.
Dismay turned to horror as we learned that wasted money was the lesser transgression; humans were actually being harmed when their physicians tried to apply to their patients what they had learned in animal labs.
Our awareness of the failure of the animal models increased as we taught in two medical schools and one veterinary school.
Penicillin, cyclosporin, heart valve replacements, the statins, antidepressant medications and many others were delayed because of misleading test results in animals. Humans died as a result of these delays.
Vaccines and drugs such as fen-phen and Rezulin, that tested safe in animals killed humans, while smoking, environmental poisons such as asbestos and glass fibers, and high cholesterol were advertised to be safe in humans based on tests in animals.
Any physician will tell you that animals are not furry-looking people when it comes to disease and treatment.
The first successful kidney transplant was performed on a human in 1954; a rat underwent a successful kidney transplant five years later.
Knockout mice that have had their genome changed to become more human-like have also been failures. Changing one or two genes out of thirty thousand will not make a human out of a mouse.
While mouse marketers and many others herald the genetically modified mouse as a breakthrough for medical research and hence those suffering from disease, in fact it is a boon only to their bottom line.
The benefits of genetically modified mice sound enticing but the actual benefits have been nonexistent.
The cystic fibrosis mouse has been disappointing as it fails to mimic the human version of the disease and among the first group of human epilepsy genes to be described (based on the study of humans), there was not one gene that had been described in animals.
Transgenic animals have failed as models for human diseases for many reasons but mainly because transgenic animals, apart from the gene in question, still have genes, organs, and systems that influence the rest of the organism thus extrapolation of what was learned from the animal model to humans is usually wrong.
This should not be surprising.
A recent study published in Science revealed that one strain of mice could have a gene removed without obvious adverse effects while another strain would die without the gene.
If one strain of mice cannot predict what will happen to another if a gene is removed we obviously cannot use them to predict what will happen in humans.
At best, animal models using genetically modified mice have been merely demonstrative and more frequently misleading and dangerous as is evident from watching the constant parade of breakthroughs from these mice that make the news everyday but that never seem to actually work in humans.
The price for the prostitution of reason in the service of romantic fantasies such as these genetically modified mice is being paid by sick and suffering humans everyday. The antidote to this self-deception is to sit by the bedside of a child who has been harmed because of the animal model and attempt to explain to the parents why this tragedy has occurred.
The great advances in science that have given us the high standard of medical care we enjoy today have come from ethical, human-based research, most notably clinical observation, epidemiology, autopsies, human tissue research, genetics, in vitro research, pathology, and post-marketing drug surveillance.
Technology-based research has given us computer and mathematical modeling; CT and MRI scanners; while the specialization of physicians, nurses, and hospitals along with reforms in public sanitation have increased the length and quality of life.
Animal experiments have only diverted funds from reliable approaches to medical research. Relying on animals to predict human response, be it to drugs or disease, is an archaic paradigm that has been replaced, in scientifically advanced environments, with modern-day research modalities like artificial neural networks, computer and mathematical modeling, pharmacogenetics, high-tech brain imaging scanners and many more. Further, we don’t need to use humans as guinea pigs nor indeed are we.
Ethical human research is conducted daily at every medical school in this country and will continue to be. Many people are alive today because of it.
Currently accepted, ethical human studies combined with new ones, such as those listed above, and old research methods such as epidemiology and autopsies will continue to give us the advances we need.
Many years ago, before Darwin’s theory of evolution, before the discovery of DNA, before scientists had access to todays technology, we were able to learn things about humans from animals. Horses have hearts, as do humans.
Monkeys have immune systems, as do humans.
But as the focus of biomedicine becomes increasingly fine-grained, as it has in the modern era, the differences between humans and other animals outweigh the similarities.
Cancer, Alzheimers, stroke, diabetes, vaccine development, drug testing, Parkinson’s disease, transplant medicine, heart disease, and AIDS are but a few of the many examples that demonstrate the subtle differences between the species that negate their utility as models for each other.
Drug testing is another good example of the failure of the animal model.
Eighty percent of all drugs that pass animal tests are withdrawn after Phase I clinical trials (on humans).
Even the pharmaceutical industry acknowledges the inadequacy of animal testing.
The romantic fantasy that animal models can be used to cure all diseases is one reason why we still have no cure for cancer, stroke, Parkinsons and other diseases.
In fact, using animals as models for human disease and drug testing is not in the best interests of human patients but is in the best interests of those who make a living doing such experiments.
The perseveration by the vested interest groups that without animal models children will die is specious.
At best animal models have been merely demonstrative and more frequently misleading and dangerous as is evident from watching the constant parade of “breakthroughs” from animal models that make the news everyday but that never seem to actually work in humans.
The public has long been sold the idea that the cures for human disease will be found in animals.
It is time the public knew that not only is that an expensive fallacy but it is also a dangerous one.