So-called model organisms have long been at the core of biomedical research, allowing scientists to study the ins and outs of human disorders in non-human subjects.
In the ideal, such models accurately recapitulate a human disorder so that, for example, the Parkinson's disease observed in a rat model would be virtually indistinguishable from that in a human patient. The reality, of course, is that rats aren't human, and few models actually faithfully reflect the phenotype of the disease in question. Thus, in the strictest sense of the word, many "models" aren't truly models at all. To developmental biologist and Whitehead Institute Member Hazel Sive, this is no small matter.
"The term model is used very loosely," says Sive. "That was a problem to me: Everything's a model!"
Sive sees the need to adopt a new term to expand the language of biological research to encompass systems that, although not technically models, can still offer tremendous utility in studying the etiology of human disorders. In this setting, she proposes the use of the word "tool."
Sive formally states her case in the March issue of Disease Models & Mechanisms. In an editorial entitled "'Model' or 'Tool'? New definitions for translational research," Sive calls for using 'tool' as a way to define a biological system that, though failing to recapitulate a phenotype, can, by virtue of its molecular makeup, provide important insights into a human disorder.
"This is not semanticthere really is a difference," says Sive. "Mice have a cachet and are thought of as similar to humans, but obviously they're really quite different from humans. Frogs, flies, fish, and yeast, are serious systems for understanding fundamental biological questions, but they're seen as less valuable when it comes to studying human disease.
Although the publicity around Sive's proposal is new, she conceived of this construct nearly eight years ago for her own rese
|Contact: Nicole Giese|
Whitehead Institute for Biomedical Research