What characterizes an oncogene?

An oncogene is characterized by its potential to promote uncontrolled cell growth and division, which can lead to cancer. In its normal state, an oncogene is referred to as a proto-oncogene, which is involved in regular cellular functions such as growth and division. However, when this gene undergoes mutations or is expressed at higher levels than normal, it can lead to a gain of function that contributes to the transformation of a normal cell into a cancerous one.

The choice that identifies an oncogene as a normal gene that can become mutated accurately captures this critical aspect of its function. Mutations in proto-oncogenes can result in proteins that are hyperactive or constitutively active, leading to the promotion of malignancy. This is why understanding the transformation of proto-oncogenes to oncogenes is essential in the study of cancer biology and therapy.

Other choices do not encapsulate the essence of what an oncogene represents: inhibiting growth is contrary to the defining characteristics of oncogenes, while the promotion of apoptosis does not align with the fundamental role of oncogenes in driving cellular proliferation rather than cell death. Finally, a gene that leads to normal cell function does not typically classify as an oncogene since oncogen