Thanks to Dr. Elizabeth Vierling, UMass Professor of Biochemistry and Molecular Biology, for her presentation on the Science of Genetically Modified Plants at the Amherst Town Hall on April 15, 2014. Sponsored by Grow Food Amherst, Sustaining Amherst, the National Science Foundation, and the League of Women Voters, the event was attended by over 50 interested citizens.
Dr. Vierling recognized that some of her colleagues thought she might be “a little bit crazy” for being willing to speak in a public forum on such a controversial topic. Nevertheless, the audience was respectful and seemed genuinely interested in learning the science.
She began with a review of the background of plant genetics and an explanation of the “chemistry of life”. A brief review of nucleic acids, proteins, lipids and carbohydrates provided the context for an understanding of DNA and the genes that make up a chromosome.
She explained that a genetically modified organism (GMO) is an organism created by extracting genes from one organism and putting it into another. The audience asked thoughtful questions about how genes are put into plants and why anyone would want to do this trick anyway!
Dr. Vierling’s personal history included a connection to some of the early research on how bacteria inject their own genes into plants to manipulate the plant to create a hospitable environment for the bacterium. This happens at times in nature and one of the results is Crown Gall, a disease of plants such as the willow tree on the right. The unique bacteria able to do this neat trick is called Agrobacterium, the “first genetic engineer.”
The same bacterial organism that is able to inject its own genetic material into plants can also be used by humans to inject other genes into plants. This is the process of genetic manipulation.
Questions from the audience were very thoughtful and demonstrated a deep curiosity about how humans have manipulated the genetics of plants.
Dr. Vierling then explained how plants are made “Roundup Ready”, that is resistant to the herbicide (weed killer) Roundup or glyphosate. Farmers spray the herbicide Roundup on crops that are genetically manipulated to be resistant, and weeds are killed by the herbicide but the crops survive. The process of creating “Roundup Ready” corn and soybeans was a bit “geeky” by Dr. Vierling’s own admission but most of the audience tried to really understand the biochemical process.
She stated that the major crop plants that have been genetically modified are corn, soybeans and cotton. Most of the acreage growing these crops are raising genetically modified types of these plants. An example of genetic modification is the use of GMO papaya in Hawaii. The ringspot virus almost wiped out the entire industry. In fact, genetic modification saved the industry.
Dr. Vierling’s curiosity and passion for the topic was infectious and her love of science was clear. She also acknowledged that the social and economic concerns associated with the use of GMO’s are important topics for discussion. As the evening concluded she thanked the audience for trying to understand the science of such a controversial topic and recommended several websites which she felt were credible sources of information: