15.8: From Genetic Engineering to Genetic Modification

Genomic, transcriptomic, and proteomic technologies have vastly increased our knowledge of how cells work at a molecular level and how genes and their regulation have evolved. We continue to add to our knowledge of the disease process and, in at least a few cases, how we can treat disease. The use of technologies to genetically engineer (i.e., modify) organisms is more controversial, despite the best of human intentions. The creators of some genetically modified organisms (GMOs) aim to rid the world of environmental waste and increase food productivity to better feed the world. The introduction of “beneficial” genes into microbes enabled the engineering of oil- and plastic-eating bacteria and food species, to create GMOs such as:

• drought-resistant crops to increase the range of land where major food crops can be grown.
• pest-resistant crops which reduce reliance on environmentally toxic chemical pesticides.
• herbicide-resistant crops which will survive the chemicals used to destroy harmful plants.

The quest for “improved” plant and animal varieties dates back to a time long before recorded history when farmers were crossbreeding cows, sheep, and dogs, as well as crop varieties from corn to wheat, in the hope that mating better with lesser varieties, all in the hope of producing faster-growing, larger, hardier, (you name it) varieties. It is the manipulation of DNA (the essence of the genetic material itself) to do the same that is at the root of the controversy. Controversy is reflected in opinions that GMO foods are potentially dangerous and that their cultivation should be banned. But the general consensus is that attempting to ban GMOs is too late! In fact, you are probably already partaking of some GMO foods without even knowing it. Perhaps the good news is that after many years of GMO crops already in our food stream, the emerging scientific consensus is that GMO foods are no more harmful than unmodified foods. The current debate is whether to label foods that are (or contain) GMO ingredients as genetically modified. In an odd but perhaps amusing take on the discomfort some folks feel about GMOs, a startup company has genetically modified petunias. When grown in water, their flowers are white, but when “watered” with beer, they will produce pink or purple flowers, depending on how much beer they get. (Check it out at Can Beautiful Flowers Change Face?) According to the company, it seeks “to bring what it sees as the beauty of bioengineering to the general public” (and perhaps some profit as well?).

Finally, new CRISPR and related tools can precisely edit any DNA sequences. While not yet ready for prime time, we already noted a CRISPR-based protocol even promises to amplify genes from DNA without prior denaturation at 37oC, and therefore without a thermocycler. Unlike the “quack medicines” of old, these tools have the real potential to cure disease, to destroy disease-carrying vectors, to cure cancer, to improve crops and possibly even alter the course of evolution. We may also need to mobilize such technologies to cope with the coming effects of climate change! The speed with which one can accomplish such good (or evil) is truly awesome.