A beautiful mouse.

When it comes to exporting quality mice, the United States heads the list with Mickey Mouse. But for a handful of Argentine scientists, Mickey Mouse takes a back seat to the TH-CRE, a species of genetically modified mouse. Such mice are used around the globe for medical and scientific research, yet the TH-CRE is different. In Argentina, scientists pair these mice with mates that carry diseases that affect humans, such as schizophrenia, Parkinson's disease and cancer. The offspring, which come down with the illnesses, later become research subjects. For Marcelo Rubinstein, who oversees the project at the Institute of Research on Genetic Engineering and Molecular Biology in Buenos Aires, the mice are Argentina's contribution to the world of genetic research. "Our work is considered a great contribution of high scientific value," Rubinstein says. In the United States, and in the U.K., institutions have begun importing TH-CRE mice to conduct research, and demand is on the rise. The laboratory, however, earns no money by exporting the mice, as it is paid in data as part of a research exchange. Yet, the program has been a shot in the arm for Argentina's scientific community, Rubinstein says. "We are usually the ones who request scientific material from outside, but this time the roles have reversed," he says.