(Science: molecular biology, oncology) Mutated and/or overexpressed version of a normal gene of animal cells (the proto-oncogene) that in a dominant fashion can release the cell from normal restraints on growth and thus alone or in concert with other changes, convert a cell into a tumour cell. A gene that causes normal cells to change into cancerous tumor cells.A viral [[ Gene causing cancer induction.
The first oncogene was discovered in 1970 and was termed src (pronounced SARK). Src was in fact first discovered as an oncogene in a chicken retrovirus. Experiments performed by dr g. Steve martin of the university of California, Berkeley demonstrated that the src was indeed the oncogene of the virus. In 1976 Drs. J. Michael bishop and Harold E. Varmus of the university of California, San Francisco demonstrated that oncogenes were defective proto-oncogenes, found in many organisms including humans. For this discovery bishop and Varmus were awarded the Nobel Prize in 1989.