Which statement about oncogenes is true?

Which statement about oncogenes is true?

• A. A normal gene that suppresses tumor growth.
• B. A protein that causes tissue differentiation.
• C. A genetic mutation that promotes clonal proliferation and cancer development.
• D. A receptor involved in immune response.

Answer: (C)

Oncogenes are mutated or overactive versions of normal genes that drive cancer by forcing cells to proliferate uncontrollably. In healthy cells, proto-oncogenes help regulate growth and division in a controlled way. When one of these genes is altered—through mutation, amplification, or chromosomal rearrangement—it becomes constitutively active, promoting clonal proliferation and tumor development. That’s why the true statement describes oncogenes as a genetic mutation that promotes cancer progression. The other descriptions don’t fit: a normal gene that suppresses tumor growth refers to tumor suppressor genes, which act to restrain growth; a protein that causes tissue differentiation isn’t the defining feature of oncogenes; and a receptor involved in immune response is not the typical role attributed to oncogenes.

Oncogenes are mutated or overactive versions of normal genes that drive cancer by forcing cells to proliferate uncontrollably. In healthy cells, proto-oncogenes help regulate growth and division in a controlled way. When one of these genes is altered—through mutation, amplification, or chromosomal rearrangement—it becomes constitutively active, promoting clonal proliferation and tumor development. That’s why the true statement describes oncogenes as a genetic mutation that promotes cancer progression. The other descriptions don’t fit: a normal gene that suppresses tumor growth refers to tumor suppressor genes, which act to restrain growth; a protein that causes tissue differentiation isn’t the defining feature of oncogenes; and a receptor involved in immune response is not the typical role attributed to oncogenes.