When DNA is bound to some of these types of particles, it is protected from being broken down and must therefore be looked upon as a source for the transfer of genetic information 3 . It was also noted that the extent of horizontal gene transfer may be far greater than classical studies have succeeded in revealing 4 . Furthermore, despite strong barriers to horizontal transfer, it was submitted that there are indications that horizontal gene transfer takes place between eucaryotes across species, family and kingdom boundaries 5 . It is extremely important, therefore, to have these two issues investigated because even exceptionally rare cases may have far-reaching, unpredictable and serious ecological consequences 6 . Change one element of the complex balance in an ecological setting or within an organism and you change everything.
Unexpected effects are therefore typical.
Even when scientists try to change the narrowest trait of an organism, the organism itself responds and adapts as a whole. For example, when tomatoes were engineered for increased carotene production, some plants did make more carotene, but often in places where they wouldn't normally produce much of the substance for instance, in the seeds, the seed leaves, and the area where the tomato breaks off the stem 7 . Other example of unintended effects were outlined by Terje Traavik. Tobacco plants were modified to produce gamma-linolenic acid. Instead the plants mainly produced the toxic product octadecatetraenic acid 8 .