The Mouse Trap
How One Rodent Rules the Lab
Ever wonder how many mice have to die to produce one peer-reviewed medical journal article? Or one new drug? And how much can we really learn about human physiology from mice or other animal experiments anyway?
Daniel Engber has authored an excellent, three-part expose at Slate that answers these and other questions about the animal research industry.
Part One, “The Mouse Trap,” looks at the realities and dangers of our dependence on cheap, couch-potato mice for medical research.
Part Two, “The Trouble With Black-6,” examines the peculiarities of the world’s largest research mouse supplier’s best-selling mouse, an inbred, alcoholic critter called Black-6.
Part Three, “The Anti-Mouse,” looks at recent research using a hairless African rodent called the Naked Mole Rat. What makes this rodent worth study? Researchers have found that it seems to be completely immune to cancer, no matter how many carcinogens it is exposed to.
Additionally, Slate put together this excellent slide show, where you can meet the 10 most common lab rodents. An excerpt from part one follows.
The Mouse Trap
The dangers of using one lab animal to study every disease
The government’s top researcher on tuberculosis—still one of the world’s most deadly infections—seems to be running a midsized wildlife park out of his Maryland home. In a modest house on a tree-lined street in Germantown, Clif Barry keeps two kinds of turtles, three veiled chameleons, two Jackson’s chameleons, six species of frogs, half a dozen fish tanks (filled with cichlids, goldfish, and piranhas, kept separately), two dogs (named Jacques and Gillian), and an Australian tree python. “I’m an animal person,” he tells me. “My house would require a zookeeper’s license if Montgomery County knew what I had.”
Twenty miles away in Bethesda, though, where Barry serves as chief of the Tuberculosis Research Section at the National Institute of Allergy and Infectious Diseases, a single animal has taken over the ecosystem. It has infested every paper and conference, and formed a living, writhing barrier to new drugs on their way to clinical trials. “We’ve always only tested things in mice,” Barry tells me by phone one afternoon. “The truth is that for some questions, mice give you a very nice and easy model system for understanding what’s happening in humans, but mice are mice, and people are people. If we look to the mouse to model every aspect of the disease for man, and to model cures, we’re just wasting our time.”
The problem, he says, begins with the three M’s. The process of drug discovery has been carried out in the same way for decades. You start by testing a new compound in a Petri dish, to find out whether it can slow the growth of a particular bacterium in culture. That gives you the smallest dose that has an effect, known as the minimum inhibitory concentration, or “MIC”—the first M. Then you move to a living animal: Does the compound have any effect on the course of disease in a lab mouse? If so, you’ve cleared the second M, and you’re ready to test the compound in the third M, man.
Each step leads to the next: No drug can be tested in man until it’s been shown to work in mice, and no drug is tested in mice until it’s been shown to have a reasonable effect in the dish. “The bad part of that,” says Barry, “is that no part of it is predictive:” A new compound that succeeds in the dish might flunk out in the mouse, and something that can cure tuberculosis in a mouse could wash out in people…
The fact that nothing gets to humans today without first passing the mouse test, says Barry, “has cost us a new generation of medicines.” … Read the rest of this article at Slate.
Comments on this article