People inherit both types.
Oncogenes carry out many functions in the cell, where they play a role in cell division.
An oncogene is like an accelerator that speeds up the changes and replication of a cancerous cell. If the body's defenses cannot stop this exponential division, cancer can develop and spread. When mutations deactivate or eliminate these control genes, precancerous cells are then free to develop into cancer and spread. Like oncogenes, normal or dysfunctional tumor suppressor genes are passed on when a cell divides.