Oncogenes arising in members of the RAS gene family are found in 20 percent of all human cancers, including lung, colon, and pancreatic. In humans, proto-oncogenes can be transformed into oncogenes in three ways, all of which result in a loss of or reduction in cell regulation.

Are oncogenes normally found in the body?

Everyone has proto-oncogenes in their body. In fact, proto-oncogenes are necessary for our survival. Proto-oncogenes only cause cancer when a mutation occurs in the gene that results in the gene being permanently turned on.

How are oncogenes found?

The first oncogenes were discovered through the study of retroviruses, RNA tumor viruses whose genomes are reverse-transcribed into DNA in infected animal cells. During the course of infection, retroviral DNA is inserted into the chromosomes of host cells.