Question

Describe two events that can activate an oncogene.

Short answer

Two events that can activate an oncogene are genetic mutation, which alters the DNA sequence of a gene, and gene amplification, which results in multiple copies of a gene, leading to overproduction of a proto-oncogene's protein.

Step-by-step solution

Understanding Oncogenes

Oncogenes are altered versions of normal genes, or proto-oncogenes, present in every cell. They control the cell's growth and differentiation. However, when they are activated incorrectly, they can lead to uncontrolled cell growth, a hallmark of cancer.

Identifying the first event - Genetic Mutation

One of the key events that can activate oncogenes is genetic mutation. Genetic mutations alter the DNA sequence of a gene. This can occur as a result of errors during DNA replication, or due to exposure to certain environmental factors like radiation or harmful chemicals. Such a mutation may change the proto-oncogene to an oncogene, which might produce an altered protein with abnormal function, leading to uncontrolled cell growth.

Identifying the second event - Gene Amplification

A second event that can activate an oncogene is gene amplification. During gene amplification, multiple copies of the same gene are produced. When this happens to a proto-oncogene, the cell can end up producing too much of a particular protein, causing uncontrolled cell growth.