*Slaps hand against forehead*
Thank you for playing, you may step down.
Mutation happens in any and all locations within the genome.
If a cancer cell has a mutation in p53 that renders it inoperable, the cancer cell has a MUCH greater chance of survival.
This is not a difficult concept.
It is like me pointing out that a full house hand is more likely to win a poker pot than two pairs, and you ask WHY someone got dealt a full house. Because sometimes when dealt card in poker, you draw a full house; other times you draw two pairs.
Sometimes a cancer has a mutation in p53 and sometimes it does not. Those that do have mutated p53 are more likely to survive, resulting in about 50% of detected cancers having a mutation in p53.
Once again, NOT a difficult concept.
And again. Oncogenes are genes associated with cancer. Cancer is unregulated cellular replication. The genes that regulate cellular replication are often Oncogenes; because a mutation of these genes that control cellular replication leads to unregulated cellular replication.
Also, NOT a difficult concept.