I thought I would just briefly explore what Genetically Modified Organisms (GMOs) actually are and some common misconceptions.
Although GMO technically refers to many products, its common use refers primarily to plants that now harbor genes which are not naturally present in the plants genome. Examples of GMO crops that you can access as a consumer in Canada would be Corn, Canola, Soy, Cotton, Papaya and Squash. Reports that there are other GM crops (eg. tomato) that you can purchase as a consumer are absolutely not true. Does GM tomato exist? Certainly – but it’s used for research purposes in the same way as Arabidopsis thaliana. Tomato, like A. thaliana is an incredibly well characterized plant system which has a number of molecular techniques developed for it and therefore making it an attractive system to perform fundamental research on.
So why do plant biotechnologists, like myself, think genetically modifying organisms is a valuable technology? It’s because as useful as traditional breeding programs are, if the genetic diversity present in a target crop doesn’t contain the trait we want to develop, then genetically engineering a modified plant is the only way to develop that trait to a useful level. It’s as simple as that. Corn, for example, like any other plant does not demonstrate a natural resistance to glyphosate (Roundup). So introducing Agrobacterium 5-enolpyruvoyl-shikimate-3-phosphate synthetase was the only way to generate that trait. Similarly, there was no resistance to papaya ringspot virus in the natural papaya population so genetic modification was the only way to save that crop, and the associated industry.
Make no mistake – humans have been genetically modifying organisms for far longer than 30 years. The image I chose to lead this article off shows what I think everyone would recognize as corn you could purchase today, contrasted with what few of us will recognize at all. The frame on the right is what our ancestors began cultivating approximately 3000 years ago. It’s called teosinte, and the genetic modifications that augmented the fruit capacity of teosinte to modern corn was obtained through thousands of years of breeding. Another prime example of breeding programs changing the genetics of plants would be that of tomatoes. What we think of as an attractive tomato – shiny, red, big – is dramatically different than what was available hundreds of years ago. In fact, the only reason tomatoes are shiny at all is because through breeding selection, farmers inadvertently chose against tomatoes that expressed the biochemical pathways which produces certain light absorbing phenolic compounds.
Genetic modification is a tool – that’s it. In fact it’s a tool that’s used to produce much more than GM plants (eg. Insulin). All we should be concerned about is if the products of this tool are safe, and of value to our society. There is over 17 years of GM crop use on the books now and no significant, documented negative effect on people or the environment.