by Art Li
GMOs are highly contentious for their presumed unhealthiness and danger to humans, and also for their questionable role in sustaining large agri-businesses and the economic frameworks they uphold. What does science say about GMO tech, and how does it intersect with the role of GMOs on the global market?
March 28, 2016
Transcript and Annotations below:
GMOs – they’re in our food. They ARE our food. They could cause cancer. But, what impacts could they have on a broader social scale? Let’s find out!
Hello! Art again here to talk about another misunderstood food, or rather, category of foods. We’ll be discussing GMOs in this mini-series – some of the science behind how they are created, their possible effects on the human body, and finally, some of the sociopolitical and economic aspects behind their use.
One thing I want to disclose before diving into some of the details is that this video is made operating under the assumption that the genetic modification of living organisms is ethical. While it is (and should be) up for debate whether or not mankind “playing God” and altering DNA, is or is not ethical, this video is intended solely to discuss the effects of GMO research and consumption in addition to the rationale for their use. I am not personally advocating for or against the use of GMOs – i merely hope to provide information for folks to make their own best decisions about the GMOs that are and will likely to continue to be present in our food and stores.
However, we can’t start talking about GMOs without first defining what they are. According to the World Health Organization, GMO stands for Genetically Modified Organism – any organism that has had its genetic material, or DNA, directly altered by biotechnological processes . DNA stands for deoxyribonucleic acid, and is the blueprint for all life on this planet. It is the substance within all living cells that contains instructions for them to self-replicate and organize themselves into the bodies we inhabit. Pretty neat stuff.
On a more detailed level, DNA holds instructions for cells on how to create proteins. If DNA is the blueprint, proteins are the building blocks for life. All of our of cells, and a lot of the junk our body produces are comprised of proteins. DNA holds the instructions for which specific proteins should be produced by our bodies at what times, and the minute differences and interactions between these proteins sum up to form our bodily processes and physical forms. The process by which DNA is translated into these proteins is called gene expression.
What GMO technology does is alter the baseline DNA that cells use as a template for gene expression. Researchers first identify a gene or DNA sequence of interest that they wish to engineer into an organism. In agriculture this is commonly a gene that produces a protein which results in herbicide resistance, drought tolerance, or improved nutrient content. This gene could be from the same organism, or it could be from an entirely different species. As an example, “golden rice” is rice that has been modified to produce beta-carotene, a nutrient that our bodies use to produce vitamin A. Genes that produce beta carotene were first identified in various different species (daffodils, bacteria, and corn). The genes were isolated and purified from their native species, and then inserted into traditional rice seeds to produce golden rice plants.
This insertion process is done primarily using either high-pressure “gene guns” to force small particles of metal coated with the appropriate DNA into the seed cells, or by using a modified strain of bacteria to infect the seeds and insert the gene. Once the gene insertion is complete, the plant can be grown to maturity and will use its own internal cellular mechanisms to express the gene as proteins. Note that GMO technology does not alter the fundamental nature of gene expression; it merely alters the instructions that the process follows, in the form of DNA.
Part of the concern around GMO usage is that this technology could be used to engineer crops, deliberately or accidentally, to produce poisonous compounds or unsafe proteins that would then be consumed by humans. However, as in the case of golden rice, many of the modifications done to agricultural crops result in the plant producing proteins that are already ingested by humans. All of the introduced compounds that aren’t normally in people food are tested and controlled per the regulations of the market in which they are sold.
Another concern is that in consuming GMO foods, humans will take on some of the genetic changes of the modified organism, resulting in cancer or other health issues. However, as we went over previously, genetic modification normally needs to be very highly targeted and also have a vector for transfer (metal particles or bacteria) in order to succeed. The GMO foods that we consume contain no such vectors – they only contain the products of gene expression. There is a common saying that “you are what you eat”, which implies that the food we eat becomes a part of us. This is only partially true. Our bodies break food down into its component proteins, which are then metabolized. We don’t incorporate DNA by eating, which is why I am not turning into a steak or an eggplant as a result of my diet. In the same way, if I was to consume golden rice, I would not myself start producing beta-carotene and turn orange – I would merely metabolize the beta-carotene present in the rice.
The GMO products that are available for consumption currently have all been fairly researched, and do not contain modifications that have a strong likelihood of affecting human consumers. However, it is important to be able to distinguish the science behind GMOs from their implementation in our society. Interpreting the scientific aspects of GMOs in a vacuum is an oversimplification of the debate around GMOs. While the technology itself may be safe, the ways it is used and abused can certainly be harmful. Next time, I’ll attempt to unpack the intent behind GMO usage and the ways that that intent is skewed by various interests and can lead to social harm.
 Stephen O. Duke, ed. Herbicide-Resistant Crops: Agricultural, Economic, Environmental, Regulatory, and Technological Aspects. CRC Press, 1995 p53-80
Art Li is a Chinese American ex-scientist who alternates between pondering the possibilities for science as a tool of liberation and eating a lot.