How Genetic Modification Works

Published Date: 02 Nov 2017

Genetically modified organisms (GMOs) can be defined as organisms whose genetic material (DNA) has been altered through scientific process. The technology is commonly known as "modern biotechnology" or "gene technology", sometimes also "recombinant DNA technology" or "genetic engineering". It allows selected individual genes to be transferred from one organism into another, also between non-related species (World Health Organization, (2013).

Genetically modified (GM) crops are created with the use of biotechnology to change their genetic composition. There are several techniques used to introduce the desired genes or ‘inactivate’ unwanted ones. Among the most common techniques include benign bacterial or viral infection (bacterial carriers), biolistics, calcium phosphate precipitation, gene splicing, gene ‘silencing’ and electroporation (World Health Organization, 2013).

How genetic modification works?

All living organisms have genes as part of their DNA structure. They are the chemical instructions for building and maintaining life; they are the blueprints for both plants and animals. They control an organism’s growth and development. By altering the genes, scientists can change the characteristics of an organism. The genetic modification of plants involves transferring DNA (deoxyribonucleic acid), the genetic material, from a plant or bacterium, or even an animal, into a different plant species.

With any method of genetic modification, the plant cells containing the new gene are allowed to develop into full plants under tissue-culture conditions. To ensure that only the modified cells grow into full plants, scientists add an antibiotic-resistant gene marker along with the new gene to be into the plant cells. When plant tissues are cultured in a solution containing phytotoxic antibiotic, only those genetically modified cells containing the marker gene are able to survive and proliferate. In today’s technology we can increasingly identify which gene or genes determine particular characteristics, the appropriate genes can now be inserted directly into the plants we wish to modify.

Current genetic modification techniques also allow for genes to be transferred between unrelated plants to other organisms. By introducing a new gene, scientists prompt the altered cell to produce new proteins or enzymes, thus enabling the cell to perform new functions. For example, the gene that helps a cold-water fish survive low temperatures can be inserted into a strawberry to make it frost-resistant.

Genetic modification in plants is often focused on improving their ability to survive in particular harsh environments, to provide greater resistance to pests and diseases, to improve nutritional qualities, and to create tolerance to certain herbicides. Genetically modified plants have also been developed to produce compounds of potential industrial use.

The most common GM plants that have been developed and commercialised include GM soy, oilseed rape, corn and cotton that have been modified to provide resistance to certain insect/ pests and tolerance to herbicides. Genetically engineered foods have had foreign genes from other plants or animals, inserted into their genetic codes.

Benefits of Genetically Modified (GM) crops

Proponents of GM crops vigorously promote them as a key component in meeting the demand for increasing food production sustainably in the Third World. Genetically-modified foods could have the potential to solve most of the world’s problem on hunger and malnutrition, as well as the mechanism to help protect and preserve the environment by increasing yield and reducing reliance upon chemical pesticides and herbicides.

Economic benefit -- Growing GM crops are costly in the beginning because of the modern biotechnology used wherein it require highly skilled people and expensive equipment. However, there is the long-term benefit of generating large profits from growing GM crops because farmers would save money on pesticides. Farmers who had adopted the use of GM crops have had higher yields and lower costs, due to fewer losses from insect damage and a more cost-effective weed and insect control. It takes a less time to produce the desired product than it does in traditional method, GM crops is precise and does not have unwanted genes (Science Daily.com, 2010).

Farmers need less herbicides with GM crops. These crops can be re-engineered to be herbicide resistant. This means that farmers would use less herbicide on their crops to kill the weeds, with little or no effect on the crop. Thus, reducing the amount of herbicide used in one season, thereby reducing the production costs for farmers and consumers (Science Daily.com, 2010). This could also reduce and possibly eliminate the use of pesticides altogether.

Better quality foods. GM crops could be improved to have the desired characteristics and quality.  These genetic modifications could significantly improve productivity for farmers and ultimately lower food prices for the consumer. Genetic engineering in plants and in agriculture include improving crop production and introducing new traits, such as enhanced nutrients, temperature resistance, or the ability to grow in saltier soils. Modified crops also have the potential to prevent outbreaks such as foot and mouth disease, which has devastated many farmers and local economies. In some cases, GM crops may yield entirely new products that are not normally derived from traditional crops—such as medicines (Science Daily.com, 2010).

Concerns/Criticisms of Genetically Modified Crops:

The principal objections on genetically modified crops fall into three categories: the general human health risk, environmental hazards and the economic implications that it could bring (McHughen, 2000, p. 127).

Human health risks -- There is also a growing concern that introducing new and unrelated genes into food plants may have an unexpected and negative impact on human health. The possibility of introducing a new gene into a plant may create new allergens or cause an allergic reaction on certain individuals. The enhancement of gene transfer through biotechnology has already been proven to "be the major route to creating new disease agents." The inability to control such gene transfer could also lead to "antibiotic resistant genes that make infections more difficult to treat." (McHughen, 2000, p. 132)

Environmental hazards – We cannot ignore the potential ecological risk of GM crops because of its ability to transfer into another species. GM crops that are resistant to pesticides, have the potential to jump from one species to another, even where the species are not related. Another concern is that crop plants engineered for herbicide tolerance and weeds will cross-breed, resulting in the transfer of the herbicide resistance genes from the crops into the weeds. These "superweeds" would then become herbicide tolerant as well and thus difficult to control.

In a related experiment, some populations of mosquitoes developed resistance to the now-banned pesticide DDT (Pollack, 2011), many people are concerned that insects will become resistant to B.t. or other crops that have been genetically-modified to produce their own pesticides. It is not possible to design a B.t. toxin that would only kill crop-damaging pests and remain harmless to all other insects (Mercola, 2012). Currently, however, the potential risk to non-target organisms is unclear and requires further evaluation.

Economic concerns -- Introducing GM foods into the market is a lengthy and costly process, biotech companies wish to ensure a profitable return on their investment. Many new genetic engineering technologies and GM plants have been patented, and patent infringement is a big concern of agribusiness (Nuffield Council on Bioethics ,1999) . Yet consumer advocates are still worried that patenting these new plant varieties will raise the price of seeds so high that small farmers and third world countries will not be able to afford seeds for GMO crops, thus widening the gap between the wealthy and the poor. It is hoped that in a humanitarian gesture, more companies and non-profits will offer their products at reduced cost to impoverished nations.

OBSERVATION & CONCLUSION

Science is not exact and "genetic engineering" is unpredictable. Inserting genes from organisms which we have never eaten before could prove to be a health hazard for many of us--new proteins would be introduced into the human body. Several research show that GM crops have the capacity to cross-pollinate with other wild species. Transferred genes of viruses and bacteria, which are the predominant medium used to create the potential for the genetic modification to create new toxins; as well as its potential for causing allergic reactions.

I agree that the application of genetic modification to crops has the potential to bring about significant benefits, including such as improved nutrition, enhanced pest resistance, increased yields and new products such as vaccines. Advocates of this technology believe that it has the potential to solve most of the world’s problems in hunger and malnutrition.

There are real risks attached to all forms of genetic modification.  Genetically engineered foods are generally regarded as safe. However, there has been no adequate testing, to ensure complete safety. I believe certain considerations like mutations and cross-pollination, etc. should be closely monitored to ensure food safety and security for present and future generations. Each new genetically engineered food will have to be judged individually. We cannot predict how the transferred gene will behave. Unlike drugs that are found to be unsafe and can be pulled from the market, genetically modified food crops are living creatures and cannot be recalled.