Final answer:
A gene that develops a mutation causing a protein to be hyperactively transcribed or that creates a protein resistant to degradation is known as an oncogene.
Step-by-step explanation:
When a gene develops a mutation causing a protein to be hyperactively transcribed or creates a protein that is resistant to degradation, the altered gene is known as an oncogene. This is because oncogenes can lead to uncontrolled cell growth by altering transcriptional activity, protein stability, or protein translation. Normally, genes that code for positive cell cycle regulators are called proto-oncogenes.
However, when these proto-oncogenes are mutated, they can become oncogenes. An example of an oncogene is myc, which is involved in Burkett's Lymphoma, leading to the transformation of normal B cells into cancerous cells.