Further, because of the complexity and interactivity of living systems and because of the extent to which our understanding of them is still quite deficient it is impossible to predict what specific problems could result in the case of any particular genetically engineered organism. Prediction is even more difficult because even when dealing with one variety of a food-producing organism and one particular set of foreign genetic material, each insertion event is unique and can yield deeply different results. The mechanics and risks of recombinant DNA technology are substantially different from those of natural methods of breeding. The latter are typically based on sexual reproduction between organisms of the same or closely related species. Normally, entire sets of genes are paired in an orderly manner that maintains a fixed sequence of geneticinformation.
Every gene remains under the control of the organism s intricately balanced regulatory system.
The substances produced by the genes are those that have been within the species for a long stretch of biological time. In contrast, biotechnicians take cells that are the result of normal reproduction and randomly splice a chunk of foreign genetic material into their genome. This always disturbs the function of the region of native DNA into which the material wedges. Further, the foreign genes will usually not express within their new environment without a big artificial boost, which is supplied by fusing them to promoters from viruses or pathogenic bacteria. As a result, these genes operate essentially as independent agents outside the host organism s regulatory system, which can lead to many deleterious imbalances.