noun
1. A normal gene that has the potential to become an oncogene.
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2. The RET proto-oncogene in multiple endocrine neoplasia type 2 and Hirschsprung's disease.
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3. The crucial implication of the Varmus and Bishop experiment was that a precursor of a cancer-causing gene—the “proto-oncogene,” as Bishop and Varmus called it—was a normal cellular gene.
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4. In the laboratory, we call this the six-degrees-of-separation-from-cancer rule: you can ask any biological question, no matter how seemingly distant—what makes the heart fail, or why worms age, or even how birds learn songs—and you will end up, in fewer than six genetic steps, connecting with a proto-oncogene or tumor suppressor.
