Mutations are what happens when the normal DNA repair mechanism fails. We repair mistakes in our genetic code all the time. For example, DNA polymerase 1, the enzyme that makes copies of our DNA during replication, has an error rate of about 1 in a million. read more
Unfortunately, if the mutation is matched by the complementary strand, it won't look any different than normal DNA and the body will not recognize that the gene is damaged. (Although, there are some more complicated examples of being able to tell something is off and triggering suicide). read more
"By actively avoiding these harmful environmental factors, we can minimise the number of mutations occurring in our body that can lead to cancer." Internationally, scientists have so far identified only one promoter mutation, known as the telomerase reverse transcriptase (TERT) gene, that definitively contributes to cancer. read more