Genetically Modified Organisms

Summary

Genetically modified organisms are produced through biotechnology and genetic engineering and involve genetic modifications in which genetic material is added or removed to alter the organism's genetic structure. Many organisms have undergone genetic modification, including bacteria and viruses, plants and animals, and even human beings. Most genetically modified organisms are created for therapeutic reasons, such as medicine and food for human consumption. Such organisms have the potential to affect all members of human society and their surrounding environment and have, therefore, become one of the most controversial ethical and ecological issues of the twenty-first century.

Definition and Basic Principles

Humans have selectively bred and crossbred plants and animals for desired traits since almost the dawn of agriculture, but advances in genetic technology have given people novel ways to manipulate plants and animals. These advances are motivated by the desire to develop new medical treatments for genetic diseases and disorders and to increase food production to satisfy the world's growing population. Most advances involve recombinant DNA technology, in which an organism's genes are altered by removing a specific gene from the cell of one organism and inserting it into the cell of another. This splicing together of gene fragments from different species produces a new organism that would not be produced through natural reproduction processes or would not be feasible because of the impossibility of interspecies breeding. This new organism is defined as a genetically modified organism (GMO). GMO food products have been on store shelves for some time. However, innovations like experimental surgery developed in the 2020s and involved organs from genetically modified animals implanted in humans.

The advancement of genetic technology and the introduction of GMOs into the human food chain has prompted controversy over the ethics of manipulating nature and the potential for GMOs in worldwide agricultural production and medicine. Although many experts state that GMOs are safe for human consumption and offer myriad benefits to humankind, others claim that the production and consumption of GMOs are unethical and untested, which means that GMOs involve unknown consequences, which could potentially be dangerous.

Background and History

The process of natural selection, first described by Charles Darwin in 1859 in his seminal On the Origin of Species by Means of Natural Selection, states that species evolve over time. Individual organisms that possess the most desired and useful characteristics survive, reproduce, and give birth to offspring. These offspring, in turn, possess the same positive characteristics. For hundreds of years, people have manipulated the process of natural selection through traditional agricultural selection and crossbreeding to create or eliminate specific characteristics in plant and animal species, producing a wide variety of cereal crops, livestock animals, and pets.

Human interference has altered many plants and animals through crossbreeding or selection, but the desirable traits initially appeared through naturally occurring genetic variation. Because the desired traits already existed, human interference in the breeding process was often viewed as relatively benign and within natural bounds. Although humans have manipulated the breeding of plants and animals based on phenotypic characteristics for a long time, the ability to directly manipulate the genotype developed much later. Specifically, medical and agricultural scientists have researched and advanced genetic modification technology to feed a growing and hungry world population and develop medical treatments.

Although genetic engineering is a phenomenon of the late twentieth century, the building blocks for such technology began with the first isolation of DNA in 1869 and the subsequent awareness of its relevance to heredity in 1928. The first accurate double-helix model of DNA was developed in 1953 by James D. Watson and Francis Crick, and the first gene sequence and recombinant DNA was created in 1972 by researchers from Stanford University. The latter discovery truly heralded the beginning of the biotechnological industry and the development of GMOs.

Genetic engineering research continued during the 1970s, and the first publicly and commercially available GMO, a form of human insulin produced by bacteria, was developed in the United States (US) in 1982. However, for the most part, the majority of commercial GMOs sold and used in the twenty-first century are found in agriculture and food production. GMO research scientists believe that genetic engineering is the only method to guarantee global food production, particularly as predictions regarding global climates have indicated that traditional agriculture practices will fail to meet demand.

How It Works

Fundamentally, the development and manufacture of GMOs replaces natural selection processes with artificial genetic manipulation. At its most basic, GMO technology relies on a sound understanding of DNA. It involves the subtraction of specific genetic material or substitution of material from one species with that from another. Genetic engineering, a complex endeavor, deals with the most fundamental building blocks of an organism. Within a cell are tiny strand-like structures called chromosomes, which contain a nucleic acid called DNA. This molecule contains all the genetic material required for inheritance and thus is the basis for genetic manipulation technology.

Initially, genetic manipulation referred to various techniques for modifying organisms through reproduction and gene inheritance. Later, however, the definition became more restricted and explicitly referred to recombinant DNA technology, a form of genetic engineering in which the genome of a cell or organism is artificially modified. The fundamental concept of this technology is that genetic material from different species is combined to create a new species or organism. That is, molecules of DNA from more than one source are united together inside a cell, which is then inserted into a new organism or host, where it can reproduce. Because the genome is passed on to offspring, the modification is considered self-perpetuating. An organism's biological activities and physical characteristics are controlled by its genome, so genome modification can significantly influence the organism's biological functions and traits. The objective behind such technology is to advance medicine and agriculture to develop more effective medical treatments and improve crop yield and disease resistance.

Applications and Products

The possible applications and products of genetic engineering are vast and limited only by the imagination. For the most part, however, the major function of genetic engineering, and hence the development of GMOs, is related to their potential in agricultural, medical, and environmental applications.

Agricultural Applications. The continuing rapid expansion of the human population is necessitating an increase in the food supply. Providing adequate food for a hungry world has become a significant issue for science. The need for food has been instrumental in promoting and advancing genetic modification techniques to produce new and improved organisms, particularly those that, for example, have higher yields or are drought and disease-resistant. Through recombinant gene technology, it has become possible to create plant species that are capable of surviving in extreme temperatures and with low rainfall, that can convert atmospheric nitrogen into a useable form (thereby eliminating the need for nitrogen fertilizer), and that can produce their own resistance to pests and pathogens (thereby eliminating the need for chemical pesticides). Versions of soybeans, canola, corn, potatoes, sugar beets, and cotton that have been genetically modified to increase herbicide tolerance and resist insects are all available for purchase.

With some specific exceptions, research and the development of genetically engineered animals has proven to be less straightforward than the genetic modification of plants and certainly more ethically problematic. In addition, although the public shows some resistance to introducing genetically modified plants into the human food chain, most people express much greater resistance to directly consuming genetically modified animals. Therefore, research on genetically modified animals for use in agriculture has stayed in a relatively early stage of development. However, there has been some research into and experimentation with the genetic manipulation of animals to increase production and meat yield. By the mid-2020s, the US Food and Drug Administration (FDA) had approved several genetically modified animals for human consumption, including the AquAdvantage salmon modified to grow twice as fast as wild salmon, GalSafe pigs modified to allow individuals with a specific allergy to consume the meat, and beef cattle with genomic edits enabling them to sustain higher temperatures through shorter coats.

Medical Applications. Although agricultural applications are very important, the potential medical applications of GMOs are even more significant. The world's first commercial applications of genetic engineering were, in fact, medically oriented and included synthetic human insulin, approved for public sale in the US by the FDA in 1982, and a human hepatitis-B vaccine, approved by the FDA in 1987. Before the 1980s, synthetic human insulin (produced from animals) was available only in relatively limited quantities. Since the 1980s, research into medical applications for GMOs has rapidly advanced. Of particular benefit is the ability of genetic engineering to produce GMOs on a previously unavailable scale.

Perhaps the most significant potential application of genetic engineering and GMOs is in the treatment and possible cure of genetic diseases. Human society is plagued with both serious diseases and mild disorders, more than three thousand of which are genetic in origin and, therefore, difficult to cure using conventional medicine. Although this technology is still in its infancy, gene therapy holds tremendous potential to assist people with genetic diseases.

The medical applications of genetic engineering were on display in March, 2024 when a genetically modified pig kidney was transplanted into a human patient for the first time in history. The surgery was expected to help hasten successful transplants of other organs, such as hearts and livers, from genetically modified pigs. It was considered a significant achievement when a shortage of organs caused long waitlists for many patients in need of transplants. In April, 2024, another patient received a genetically modified pig kidney during surgery at New York University Langone Health, signaling the procedure could occur with increasing frequency.

Environmental Applications. Increasing human populations is an important issue concerning agricultural food production and its environmental impact. Genetic engineering and GMOs could solve some of the world's most serious ecological problems. Research has produced genetically modified viruses that can be used to create ecologically friendly lithium batteries, modified bacteria that can produce biodegradable plastic, and genetically manipulated bacteria encoded for bioremediation. Genetic modification technology may even be useful in the fight for the survival of some of the world's most vulnerable and endangered species.

Careers and Course Work

Students who wish to pursue a career in genetic engineering usually obtain an undergraduate degree in science or medicine. Typical majors include molecular biology, biomedical engineering, and genetics, although some universities offer specific undergraduate courses in genetic engineering. Graduate studies are essential for those wishing to pursue a career in genetic engineering. Following graduation, students studying genetically modified organisms will understand methods and processes involved in recombinant DNA technology and techniques, including DNA cloning, recombining genes, nucleic acid hybridization, gel transfers, and DNA sequencing.

Genetic engineering, while controversial, certainly offers the potential as a significant tool in solving problems in agriculture, medicine, environmental science, and basic biology. Genetic technology will likely play a central role in almost all areas of innovative biological sciences. Rapid advances in the field correspond to significant career potential and multiple avenues. Students involved in genetic engineering research and the application of GMOs can pursue careers in medical diagnosis, treatment, and gene therapy, agricultural food production, environmental bioremediation, and resource management within the private sector, nongovernmental organizations, specialized government organizations and agencies, and universities undertaking teaching and research.

Social Context and Future Prospects

Genetically modified organisms could be very advantageous to people. Specifically, scientists claim that GMOs will be vital to the future of food production and therapeutic medicine. Given the reality of climate change due to global warming, crops that can produce higher yields, resist pests and pathogens, and better tolerate drought are very attractive. The ability to create nutrient-dense crops could also aid in solving world hunger and the imbalance of worldwide resources. The use of GMOs in the treatment of genetic disorders makes them potentially life-saving. Supporters of GMO technology argue that genetic engineering has become an economic and environmental necessity regarding agriculture, environmental bioremediation, and medicine.

Despite their apparent benefits, GMOs are often not well-received by the public. Surveys in some countries have revealed that most people are against the creation and production of genetically modified foods, animals in particular. This opinion is shared by many environmental organizations which claim that the undeniable benefits of GMOs are far outweighed by their possible effects on ecosystems, native flora and fauna, and human health. Of particular concern is that the potential risks of GMOs are as yet unknown. Opponents of GMO technology have stated that imposing GMOs onto the public without long-term, rigorous testing is irresponsible and that more research is required.

Critics of GMOs have also argued that the FDA should play a more significant role in testing the safety of these products and regulating their sale. However, in 2015, the FDA instituted a new rule stating that foods containing genetically modified ingredients from sources approved by the FDA do not necessarily need to have a label identifying these genetically modified ingredients, leaving that choice up to the producer. Additionally, the organization released a statement stipulating that it preferred using terms, such as "not bioengineered" over "non-GMO" on any labeling. Many people expressed disagreement with these decisions. That same year, the FDA reiterated that it did not have any substantive evidence proving that GMOs differ significantly from their natural counterparts or presented any greater safety risk. Around the same time, the FDA officially approved the first genetically modified animal for sale in the US food market, salmon. After analyzing data submitted by the manufacturer of the fish, the FDA found that the salmon was safe to eat by both humans and animals and that its genes remained stable throughout generations. Two other genetically modified animals followedpig and beef cattle. 

In the summer of 2016, a law was passed by Congress and signed by President Barack Obama, requiring the US Department of Agriculture (USDA) to define the regulation for implementing a nationwide requirement to label any food products that have been genetically modified or contain genetically modified ingredients. Two years later, the USDA released its National Bioengineered Food Disclosure Standard, using the term "bioengineered" and providing a definition of what classifies a food as bioengineered and a list of worldwide agricultural products with a bioengineered form for reference. Implemented at the beginning of 2020, manufacturers and retailers were given two years to achieve mandatory compliance, with options for conveying the information on packaging that included a symbol, a digital link, and plain text.

Bibliography

"BE Disclosure." Agricultural Marketing Service, US Department of Agriculture, www.ams.usda.gov/rules-regulations/be. Accessed 5 June 2024.

Bertheau, Yves. Genetically Modified and Non-Genetically Modified Food Supply Chains: Coexistence and Traceability. Wiley, 2012.

Diaz, Julia M., et al. "Genetically Modified Organism." Britannica, 15 Nov. 2024, www.britannica.com/science/genetically-modified-organism. Accessed 10 Dec. 2024.

“GMO Crops, Animal Food, and Beyond.” US Food and Drug Administration, 5 Mar. 2024, www.fda.gov/food/agricultural-biotechnology/gmo-crops-animal-food-and-beyond. Accessed 4 June 2024.

"How GMOs Are Regulated for Food and Plant Safety in the United States." US Food and Drug Administration, 17 Feb. 2022, www.fda.gov/food/agricultural-biotechnology/how-gmos-are-regulated-food-and-plant-safety-united-states. Accessed 5 June 2024.

Howe, Christopher. Gene Cloning and Manipulation. 2nd ed., Cambridge UP, 2007.

Neergaard, Lauren. “New Jersey Woman Becomes Second Patient Ever to Receive Pig Kidney in 'Transformative' Surgery.” PBS, 24 Apr. 2024, www.pbs.org/newshour/health/new-jersey-woman-becomes-second-patient-ever-to-receive-pig-kidney-in-transformative-surgery. Accessed 4 June 2024.

Nelson, Gerald C., ed. Genetically Modified Organisms in Agriculture: Economics and Politics. Academic, 2001.

Newton, David E. GMO Food: A Reference Handbook. ABC-CLIO, 2014.

Nicholl, Desmond S. T. An Introduction to Genetic Engineering. 3rd ed., Cambridge UP, 2008.

Primrose, Sandy B., et al. Principles of Gene Manipulation. 7th ed., Blackwell, 2010.

Stein, Rob. "First Human Transplant of a Genetically Modified Pig Kidney Performed." NPR, 21 Mar. 2024, www.npr.org/sections/health-shots/2024/03/21/1239790816/first-pig-kidney-human-transplant. Accessed 5 June 2024.

Strom, Stephanie. "F.D.A. Takes Issue with the Term 'Non-G.M.O.'" The New York Times, 20 Nov. 2015, www.nytimes.com/2015/11/21/business/fda-takes-issue-with-the-term-non-gmo.html. Accessed 5 June 2024.

Tutelyan, Victor. Genetically Modified Food Sources: Safety Assessment and Control. Elsevier, 2013.

Watson, James D., et al. Recombinant DNA: Genes and Genomes—A Short Course. 3rd ed., Freeman, 2007.

Young, Tomme R. Genetically Modified Organisms and Biosafety: A Background Paper for Decision-Makers and Others to Assist in Consideration of GMO Issues. International Union for Conservation of Nature, 2004.