ABSTRACT
Frequent detection of amplified oncogenes in tumors indicates that amplification occurs readily in tumor cells. DNA amplification is one manifestation of the genetic instability that is typical of cell lines and tumors. Amplification of a defective butyrylcholinesterase gene has been demonstrated in blood cells from a man and his son exposed chronically to organophosphorus insecticides. Drug-resistant variants of cell lines can result from mutations of various kinds, including gene amplification. By analogy with mutator bacterial and cell strains, cells with increased amplification rates were called “amplificator.” Since amplification of a single gene is relatively rare, the rationale for isolating amplificator mutants was based on the assumption that a cell with simultaneous amplification of two unlinked genes was likely to have a generally increased ability to amplify its DNA.
