Oncogene

Part of speech: noun

Pronunciation: /ˈɒŋkə(ʊ)dʒiːn/

Definitions

1. A gene that, when altered by mutation, can promote the development of cancer by transforming normal cells into cancerous ones; it influences processes such as cell growth and differentiation; activation of these genes can disrupt normal regulatory mechanisms
2. A gene associated with the initiation and progression of cancer following mutation or aberrant expression; it typically regulates pathways involved in cellular proliferation and survival; they often enable cells to bypass normal growth controls
3. A type of gene that has the potential to cause cancer when mutated, it plays a critical role in controlling cell division and can lead to uncontrolled cellular growth

Etymology: The Greek "ónkos" meant a swelling or bulk, and it gave modern medicine the prefix "onco-", used in names for the study of tumours. Its partner, "gene", is a much newer coinage: the Danish botanist Wilhelm Johannsen introduced it in 1909 as a neutral label for the units of heredity. Put together, "oncogene" simply means a gene connected with tumours, formed in the same way that scientists built many other technical terms from Greek and Latin parts. The combination describes a gene that can drive cancer when it is altered or switched on at the wrong time, which is why it was named for its link to swellings rather than for any normal biological role. The word was built on the prefix, so it reads as a label for a category of genes rather than for a single one.