Argument: Conventional foods have always involved genetic tampering
"The real GM food scandal". Prospect. November 2007 - Indeed, the nature of GM technology makes it unlikely that it is more dangerous than conventional farming. Throughout history, farmers have sought to improve their crops by cross-breeding plants with desirable characteristics. Cross-breeding, however, is a lottery and its consequences cannot be easily predicted. Small genetic changes that are desirable may be accompanied by others that are undesirable. It may take generations of back-crossing to eliminate unwanted characteristics. The process is therefore not only unpredictable but slow and expensive, and may even be risky. One of the most effective standard methods of breeding to obtain improved crops is to bombard seeds and plants with gamma rays to alter their DNA by causing mutations, some of which can then be selected for a desired trait. (Incidentally, organic farmers, in their desire to avoid artificial chemicals, are even more dependent than conventional farmers on crop varieties generated by irradiation.) Irradiation alters both chromosome structure and genome sequence in a way that is quite random. Moreover, there is no legal requirement to test such irradiated products either for effects on health or for what they might do to the environment. By contrast, genetic modification in the laboratory introduces a well-characterised gene or genes into an established genetic background without big disruption. What such modification does is what plant breeding has always done, but more quickly and accurately. Opponents often argue that GM technology is different because it can transfer genes between species. But again, this is nothing new, as during evolutionary time genes have moved between species naturally. That is why we have such a diversity of plant life.