B. Examples 1. This is the most frequently altered gene in human cancer yet found. Its product negatively controls cell division. Human papilloma virus has gene products that bind to both Rb and p53 gene products. Oncogene main points 1.
Oncogenes are genes that promote division.
When they are normally active and normally regulated they don't cause cancer. If they are too active, this can be a step leading to cancer. Tumor suppressor genes are the opposite of oncogenes. When they are not active enough, this is a step leading to cancer. The DNA loses some methyl groups.