Genetic modification refers to the ability, discovered about 30 years ago, to move genes from one organism to another. Since the DNA genetic code is universal, genes from one organism can work in any other. In this sense the technique can be used within any living system.
- can everything with genes be modified / can it be done on humans?
Yes. In theory, any organism containing genes can be modified, even humans, though such modification is illegal in all (most?) advanced countries. Nevertheless, practical and functional methods have not been developed for all types of organisms.
- is spraying crops with pesticides classed as genetic modification?
No. Spraying crops with pesticides has no impact on the crop's genetic material. Pesticide application has been is a normal practice in conventional agriculture for many years and is strictly controlled.
- is it a speeding up of a natural process like the survival of the fittest?
Not really, although if the modified plant or micro-organism is better adapted to the environment than its unmodified precursor, it may occasionally be fitter in nature. This is the reason for strict controls on laboratory and fieldwork until there is enough information on how any new GM organism will actually behave (though how long that will be, and what will satisfy the regulatory authorities in that regard, is far from clear). However, field experiments have shown that most genetically modified organisms, and indeed most domesticated crops, are not well adapted to compete in nature, and do not survive unless they have a competitive advantage.
M.J. Reiss and R. Straughan (1996). Improving Nature? The science and ethics of genetic engineering, Cambridge University Press.
A. McHughen (2000). A consumer's guide to GM food - from green genes to red herrings, Oxford University Press.
M.N. McGloughlin and J.I. Burke (2000). Biotechnology - present position and future developments, Teagasc.
A. Ryan et al. (1999) The scientific basis of genetic modification, in Genetically Modified Crops: the ethical and social issues. Nuffield Council on Bioethics, 19-36. www.nuffieldfoundation.org
A series of articles in the Journal of Commercial Biotechnology, 1999, 6, pp. 93-175 and 2004, 10, 197-272.