In 1946, it was discovered that deoxyribonucleic acid (DNA) could be transferred from one species to another species, which gave rise to the idea of creating genetically modified organisms (GMO). The first breakthrough in genetic engineering of plants came about 40 years after the above-mentioned discovery in the form of antibiotic resistant tobacco (Bawa & Anilakumar, 2013). Some of the resistance-conferring genes transferred into the plants have toxin producing capabilities, which have made GM crops a prime target for many social and ethical debates (Grover et al., 2014).
Steps in GM crop production
Eukaryotic organisms are made up of DNA, which consists of the same four nucleotides, namely, Adenine, Guanine, Thymine and Cytosine. This similarity in the basic structure of the genome across many species makes it possible for insertion of gene fragments from a potential donor into a potential target organism. The fact that the target organism can transcribe the inserted foreign gene to produce the desired protein when inserted in the right place within the target organism’s genome is the very foundation on which the basic principles of genetic modification rest (Borém & Fritsche-Neto, 2014).
The process of production of a genetically modified plant commences with the identification and isolation of the gene of interest from a donor organism, which is then, cloned using vector plasmids along with a marker gene to enable the identification of a successful transformation. The construct is then transferred into competent Escherichia coli cells. If Agrobacterium tumefaciens is used, Ti plasmid is the preferred vector. The second step is the preparation of the recipient cell, which involves isolation of the plant protoplasts using explants and enzyme solutions. The third step is DNA transfer, which can be done via A. tumefaciens-mediated DNA transfer, electroporation, particle bombardment/ballistic method or treatment with PEG. The target plant cells are incubated with the gene of interest to facilitate DNA transfer (Borém & Fritsche-Neto, 2014).
In all the four methods, the aim is to transfer the gene of interest into the target plant’s genome to bring about genetic modification. The rate of transformation is usually quite low and hence necessitates the need for the selection marker gene to isolate the cells that have successfully transformed. The transformed protoplasts are pluripotent and hence have the capacity to regenerate from an undifferentiated mass of cells to rooted whole plants when subjected to the rooting medium and growth environment. Such regenerated GM plants are then self-fertilized to obtain large quantities of GM progeny, which now express the desired gene (Borém & Fritsche-Neto, 2014).
Social and ethical implications of GM crop plants
Benefits of GM crop plants
Literature suggests that apart from providing food security to nine billion people by the year 2050, planting GM crops would remediate the need for frequent tilling of soil (Green, 2012). Growing GM crops works out much cheaper than growing conventional or organic crops and tend to use less herbicide (Green, 2012). Farmers in African countries have been immensely helped by transgenic crops such as herbicide-resistant crops to fight menacing weeds such as Striga hermonthica and S. asiatica (Green, 2012). Studies suggest that GM crops immensely increase productivity and reduce loss to growers. Studies also shed light on the similarity of the end-products derived from conventional crops and GM crops, which showed no difference in composition, thereby suggesting that GM crops are safe for consumption (Bawa & Anilakumar, 2013). GM crop plants are nutritionally enhanced to provide a better quality of food to consumers (Starr, Evers & Starr, 2016).
Risks of GM crop plants
The literature is filled with claims that oppose the use of GM food. For example, the study by Aris and Leblanc (2011) suggested that herbicide resistant GM crops have a tendency to accumulate the herbicide. Similarly, Bøhn et al. (2014) suggested that GM crops such as GM soybean were nutritionally inferior to conventional crops while López et al. (2012) suggested that glyphosate-based herbicides, which are a popular choice when using GM crops, could have teratogenic effects. Studies on Bacillus thuringiensis (Bt) toxins indicate that the Cry proteins could interact with glyphosate herbicide and cause kidney problems (Mesnage et al., 2013). Studies suggest ill effects such as allergenicity, ill effects of exogenous proteins formed from the transgenes and possible instability of the transgene (Ho, 2013).
Social and ethical implications
The socio-ethical debate surrounds three major issues, namely, the unnaturalness of the GM crops, health hazard that could arise from the inserted transgenes and the non-labelling of GM food (Weale, 2010; Premanandh, 2011).
Unlike selective breeding, in which organisms of the same species are interbred, GM technology uses transgenes from unrelated species, which is considered unnatural (Weale, 2010). Supporters of GM technology believe that transferring selective genes artificially is no different from natural selective breeding (Weale, 2010). As mentioned earlier, GM crops have exhibited potential health hazards in non-human models; however, there is a lack of research on humans to corroborate the risk of using GMO crops. The non-requirement of GMO labeling on food products if the GM product presents “substantial equivalence” as allowed by the FDA is another major ethical issue. The idea of labeling the products that are derived from GM crop plants could be bad for business as it might spook potential consumers. Proponents of non-labelling of GM plants argue that the act of labeling will make GM crops cost 30% more than conventional crops, which would defeat the purpose of growing GM crops for fighting hunger. In addition, growing GM crops require intensive safety testing, which would ensure that product derived from GM plants are “substantially equivalent”. On the contrary, it is unethical to conceal the genetic nature of the crop from the public because consumer has the right to know the consistence of the product, in addition, hidden specifications might hurt customer’s personal, religious and spiritual beliefs (Premanandh, 2011). This information comes into the light where 80% of Hawaiian papaya, 13% of zucchini, 90% of sugar are GM crops (Weale, 2010).
Personal viewpoint
When looking at evidence that the opposition has provided regarding the apparent risks of GM crop plants, it is clear that the opposition has not made any breakthrough in proving actual and tangible risks of GM crops to humans. GM crops have been around for a couple of decades now without any news of major health concerns to humans. The evidence that opposes GM technology are all but "ifs and buts”, whereas the evidence supporting GM crop plants are concrete and sound. For example, GM crops have proven their worth to humanity by being less expensive, being nutritionally superior, being easier to produce and being resilient than conventional crops. To bridge the gap between the public perception of GM crops and the benefits provided by GM technology, it is necessary to come up with proper framework and regulations. For example, the issue of non-labelling could be addressed such that it benefits the farmer as well as the consumer, along with low cost of labeling. In my opinion, the future needs GM crops because there are going to be many mouths to feed and not enough supply of food.
References
Aris, A., & Leblanc, S. (2011). Maternal and fetal exposure to pesticides associated to genetically modified foods in Eastern Townships of Quebec, Canada. Reproductive Toxicology, 31(4), 528-533.
Bawa, A. S., & Anilakumar, K. R. (2013). Genetically modified foods: safety, risks and public concerns—a review. Journal of food science and technology, 50(6), 1035-1046.
Bøhn, T., Cuhra, M., Traavik, T., Sanden, M., Fagan, J., & Primicerio, R. (2014). Compositional differences in soybeans on the market: Glyphosate accumulates in Roundup Ready GM soybeans. Food Chemistry, 153, 207-215.
Borém, A., & Fritsche-Neto, R. (2014). Biotechnology and plant breeding: Applications and approaches for developing improved cultivars. Elsevier.
Green, J. M. (2012). The benefits of herbicide‐resistant crops. Pest management science, 68(10), 1323-1331.
Grover, A., Ashhar, N., & Patni, P. (2014). Why genetically modified food need reconsideration before consumption?. Journal of family medicine and primary care, 3(3), 188.
Ho, M. W. (2013). The new genetics and natural versus artificial genetic modification. Entropy, 15(11), 4748-4781.
López, S. L., Aiassa, D., Benitez-Leite, S., Lajmanovich, R., Manas, F., Poletta, G., & Carrasco, A. E. (2012). Pesticides used in South American GMO-based agriculture: A review of their effects on humans and animal models. Advances in Molecular Toxicology, 6, 41-75.
Mesnage, R., Clair, E., Gress, S., Then, C., Székács, A., & Séralini, G. E. (2013). Cytotoxicity on human cells of Cry1Ab and Cry1Ac Bt insecticidal toxins alone or with a glyphosate‐based herbicide. Journal of Applied Toxicology, 33(7), 695-699.
Premanandh, J. (2011). Global consensus–Need of the hour for genetically modified organisms (GMO) labeling. Journal of Commercial Biotechnology, 17(1), 37-44.
Starr, C., Evers, C. A., & Starr, L. (2016). Biology today and tomorrow without physiology (5th ed.). Boston, MA: Cengage Learning.
Weale, A. (2010). Ethical arguments relevant to the use of GM crops. New biotechnology, 27(5), 582-587.
