A Model Mouse
Can an accidental rodent strain unlock secrets of rheumatoid arthritis?
By John Travis
When it comes to biomedical research, it’s a zoo out there. To understand and develop treatments for human diseases, scientists are increasingly turning to monkeys, dogs, rodents, and other animals with seemingly related conditions or symptoms. In part because of biologists’ growing capability to genetically engineer mice, the number of these animal models has exploded over the past decade. Jackson Laboratory in Bar Harbor, Maine, which sells mice for research, lists more than 2,500 rodent strains in its catalog and adds about 100 annually. Scientists have used these animals to study such diverse conditions as diabetes, osteoporosis, obesity, cancer, Alzheimer’s disease, and infertility, and the work has led to new treatments.
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Yet how completely does an abnormality in a particular mouse or other animal actually emulate a human disease? That’s a question that biomedical investigators regularly confront. Sometimes it’s difficult to determine whether the animal model and human disease share an underlying mechanism. Consider the controversial mouse strain that develops a condition closely resembling rheumatoid arthritis, an inflammatory disease that degrades the joints of more than 2 million people in the United States.