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oncomouse

n. A type of laboratory mouse that has been genetically modified to carry an activated oncogene, increasing its susceptibility to cancer.

Wikipedia
Oncomouse

The OncoMouse or Harvard mouse is a type of laboratory mouse (Mus musculus) that has been genetically modified using modifications designed by Philip Leder and Timothy A Stewart of Harvard University to carry a specific gene called an activated oncogene ( v-Ha-ras under the control of the mouse mammary tumor virus promoter). The activated oncogene significantly increases the mouse’s susceptibility to cancer, and thus makes the mouse suitable for cancer research. The rights to the invention were owned by DuPont until recently. The USPTO found that the patent expired in 2005, which means that the Oncomouse is now free for use by other parties (although the name is not, as "OncoMouse" is a registered trademark).

Patent applications on the OncoMouse were filed back in the mid-1980s in numerous countries such as in the United States, in Canada, in Europe through the European Patent Office (EPO) and in Japan.