A lot of discussion is going on right know whether or not it is healthy and acceptable to cultivate and eat genetically engineered organisms (GMOs)- in particular plants. The amount of information available is immense and mostly gives an impression of an uncontrolled development of plants with unpredictable properties. In this article I want to shed light on what genetic engineering is and what a genetically engineered plant is able to do. My research consists of engineering enzymes for a better performance towards a specific reaction and genetic engineering is the main method by which new enzyme variants are created. In the relation to that the ethical issue of genetic alteration is later discussed exploring the most common examples and related topics of genetically engineered crops, for example the case of the Lenape potato, Bt-corn, the ice-minus bacterium, golden rice and virus-resistant papaya.
All definitions in literature describe that genetic engineering comprises of altering an organism on the genetic level- meaning they differ in their DNA from the naturally occurring organism- the so-called wild-type. An important distinction has to be made between transgenic and cisgenic modified organisms. If a genetically modified organism is transgenic, the gene from another organism was introduced into the organism- mostly into the inherent genome. The genome describes the sum of all DNA found in an organism. Cisgenic means that the gene came from an organism within the same or closely related species that can also be interbred with traditional methods. A genetically engineered or modified organism expresses a gene that has been introduced by genetic engineering methods. Gene expression means that the organism takes the “blue-print” -the DNA- and produces the corresponding protein. The expression genetically engineered organisms can interchangeably be used with genetically modified organisms- “GMO” in short.
All genes are coded in the DNA (DeoxyriboNucleic Acid). DNA is a long linear macromolecule that is made up off 4 different bases (specific chemical molecules) in a specific order. This set-up is universal in all organisms. Therefore, when talking about a introducing a new gene into an organism, a chemical molecule is introduced into the organism that is made up of the same chemical structures as the inherent genome of the organism. The universal genetic code makes it possible that the new gene can be read by the inherent translation machinery that converts the gene-“blueprint” into a protein. All proteins are made up of the same 20 amino acids in different sequence and length. Specific proteins are also called enzymes. An enzyme catalyses a chemical reaction. A catalyst- here the enzyme- is necessary to make chemical reaction occur that does not occur spontaneously. To illustrate an example for a spontaneous reaction- if you add baking soda to a coke bottle you will create a rigorous fountain of coke because of the now gaseous carbon dioxide. The most well-known and ubiquitous example for a catalyzed reaction is the use of a catalyst for the exhaust fumes of cars- where toxic carbon monoxide is turned in to carbon dioxide. An enzyme does the same-it turns one molecule into another molecule. The sum of all these reactions is called the metabolism of an organism. When another gene is introduced, a new enzyme or a better variant of an enzyme is expressed or produced. This new enzyme catalyses a reaction the organism could not do before or a natural reaction is performed faster. This leads-for example- to enhanced growth.
Searching the web for information on GMOs reveals a plethora of information available, a fearful portion of it I would categorize as “pseudoscience”. Populist articles often miss scientific citations for the appropriate sources or outdated and falsified information. Therefore I would like to discuss the ever-present examples and general procedures.
The public is usually weary about eating genetically modified food. What are the most common fears that are connected to GMOs? Let´s discuss of the arguments provided by for example www.rawfoodlife.com . One of the arguments is that genes are mobile (parts of genes relocate throughout the genome) and can create new variations of a plant. These new variations can lead to the production of new proteins and molecules in the plant that we eventually eat. However, not only genetic engineering can lead to this mix-up, but also methods considered as conventional breeding methods. I would like to introduce the case of the Lenape-potato  to illustrate this more clearly. It is a conventionally bred potato that had outstanding qualities regarding pathogen resistance and produced excellent potato chips. But it also contained high levels of the toxin solanine. To explain how that came about, one should know that every potato contains solanine to some extent. Only in the Lenape-potato-case the mutation of the genome caused that the production of solanine was increased. That also accounted for the good pathogen resistance. The point in comparing the Lenape-potato-case to GMOs is that there is actually not that much of a difference as far as risk is concerned. In both cases the genetic material is altered, for conventional breeding it can lead to cases like the Lenape-potato because the genome is randomly altered. The difference for explicitly modified organisms is that in that case we know which alteration we introduce into the organism. From my standpoint it can be compared to randomly pushing buttons on an unknown machine (Lenape-potato-case) versus pushing buttons after consulting a logbook of former observations what these buttons did (genetic engineering).
I also want to go into another aspect of the putative threat of unwanted new molecule production. It is important to know that enzymes can catalyze not only one but multiple reactions. Of course there are examples that there are incredibly fine-tuned enzymes by evolution to one specific reaction because survival depends on it. But for less crucial enzymes that is not the case. The scientific term for this is “catalytic promiscuity”. This principle is currently exploited by many scientists and is part of my research towards a greener chemistry. The catalytic promiscuity of an enzyme causes the enzyme not to have one product as an outcome but an array of products. It can be compared to a spray can to some extent. It always gives the object in front of it a specific colour. The shape or make of the object does not matter. With this background one can assume that the wild-type plant in its respective environment has already performed all possible reactions “by accident” with all possible molecules that are available. Therefore all possible reactions have already been “tested” by the wild-type organism. From that I would conclude that it is highly unlikely that a new “superorganism” is created that can do a complete new array of chemical synthesis. There is however the concentration issue, some substances are beneficial in small amounts but harmful in large amounts. Apart from that, every newly developed “food” has to be tested for its potential harmfulness which for example revealed the toxicity of the aforementioned Lenape-potato. All genetically engineered plants have to go through a rigorous approval process by for example the FDA.
A popular term popping up to negatively describe GMOs is “Frankenfood” . Frankenfood is a negatively value-laden word for edible GMOs. It draws the analogy to the classic novel “Frankenstein” by Mary Shelley (1818), where Dr. Frankenstein creates a monster from “lifeless matter”. If one would strictly stick to this analogy, it will become obvious that it is erroneously drawn. The monster in the book is created from “non-living” matter. That is not the case for GMOs. To date it is not possible to create a living organism from scratch- just starting from DNA, which I would consider the “non-living” matter. GMOs are organisms that are to a large extent identical to its wild-type counterparts- meaning the organism present in nature. From my point of view it can be seen as adding a trailer to a car. You enhance the utility of the car by enlarging transportation volume but you don´t change the inherent purpose of the vehicle. If you transfer this example to GMOs, the new or altered gene makes up a very small portion of the entire genome of the plant. It is quite popular to refer to GMOs in negatively associated terms, for example in German it is widely referred to as “genmanipulierte Organismen” which translates to “Genetically Manipulated Organisms”. The correct translation is “GVO- GenVeränderter Organismus” instead of “GMO” which incidentally could also be seen as abbreviation of “GenManipulierter Organismus”. But of course “manipulated” fits more into the concept for fear-mongering.