A genetically modified organism (GMO) is an animal, plant,
or microbe whose DNA has been altered using genetic engineering techniques.
For thousands of years, humans have used breeding methods to modify organisms.
Corn, cattle, and even dogs have been selectively bred over generations to have
certain desired traits. Within the last few decades, however, modern advances
in biotechnology have allowed scientists to directly modify the DNA of
microorganisms, crops, and animals.
www.nationalgewogrpahical.org.
10 Advantages and Disadvantages of
GMOs
Genetically modified organisms or GMOs are a product of a form of
scientific farming, where crops are administered with chemicals to increase
their sizes and yields. It is becoming more and more common in many
types of food we see every day. But due to its concept, it has been a topic
in heated debates around the world, with proponents and opponents
pushing their arguments. Here are the critical GMOs advantages and
disadvantages:
List of Advantages of GMOs
1. They offer more useful knowledge for genetics.
The mapping of GMO genetic material has increased knowledge about
genetic alterations and paved the way for the enhancement of genes in
crops to make them more beneficial in terms of production and human
consumption. For instance, crops can be engineered to resist unfavorable
temperatures or produce higher yields, thus providing a greater level of
genetic diversity in regions where climate hinders productivity.
2. They allow for more profit.
GMOs have become a very efficient means for farmers to make larger
profits, as it allows them to spend less time on resources. It is also
economically efficient in a way that these organisms are designed to be
pest-resistant, eliminating the need to use pesticides, which means more
savings.
3. They add more value to crops.
Another great reason to grow GMO crops is that these plants will get added
nutritional value, especially among those that previously lack the necessary
vitamins and minerals. As there are regions around the world that heavily
rely on rice or corn, plant genes can be added to such crops to boost their
nutritional value, which is particularly helpful in malnourished populations.
And because GMOs are able to resist pests and other plant diseases, crop
yields will be increased without the farmers having to use pesticides.
4. They are known to decrease the prices of food.
Advanced crops and higher yields certainly mean lower costs, which are a
benefit that can be passed to the consumers in the form of cheaper food
products. This will be very helpful to families who cannot afford to buy
supplies for everyday consumption. This also means that starvation will be
prevented.
5. They yield products that are found to be safe.
After precise testing and evaluation of GMOs and other related products,
they are found to be safe for human consumption. In fact, study shows that
they are even safer compared to traditional crops.
List of Disadvantages of GMOs
1. They would make plants that leave unwanted residual effects to
remain in the soil for a long period of time.
The process of growing GMOs includes the addition of new genetic
material into a crops genome, and similar to bacterial genetic engineering
in agricultural ecology, this means the introduction of new genes in crops,
like corn. Experimental cultivation of these crops started in the US and
Canada in the 1980s and became large scale and commercial in the mid
1990s. Now, research on the effects of large-scale growing of GMOs has
revealed various concerns on ecosystems with GMO strains, which are
believed to have the potential to alter agriculture. Particularly, GM plants
had left unwanted or residual effects remaining in the soil for extended
periods of time after they were removed, alerting agricultural regulators.
Data shows that despite the absence of the genetically modified plants,
their strain persisted for up to 6 years.
2. They can pose a threat to the insects that are important to the
ecosystem.
GM crops are said to be dangerous to some insects, as their genes could
be deadly to them. This is definitely a serious issue when it comes to
certain insects that are useful to the ecosystem, such as butterflies, and are
not actually dangerous to crops.
3. They can produce more weeds and can threaten the lives of
animals.
Engineered plants are found to function as mediators to the transfer of
genes to wild plants and the creation of weeds. To keep them under
control, scientists are inventing new herbicides that were not necessary for
non-GMO weeds and are toxic to various animals that feed on GMO crops,
such as cows. Tests have shown the uptake of these herbicides having
toxic consequences on certain organisms and the ecosystem in general.
4. They threaten crop diversity.
Those who oppose the creation of GMOs push their argument with regards
to the effect of these products on genetic diversity. They say that genes
from GM crops can spread to organic farm crops, threatening diversity in
agriculture. If it does happen that crop diversity decreases, this will have a
serious impact on the population dynamics of other organisms and the
entire ecosystem. While the chance that the strain of one genetically
modified crop could pollinate an already existing non-GM crop is
unpredictable and unlikely, as there are certain conditions to be met for
cross pollination to occur, a large-scale plantation has the ability to release
a GM strain during pollination, thus increasing the risk. As a result of the
cross pollination to non-GM plants, hybrid strains are created, which means
there is a greater chance of ecological novelty to occur. New artificial
strains will be introduced into the ecosystem that can potentially decrease
the level of biodiversity through competition.
5. They are believed to change the field of agriculture in a negative
way.
Research on the effects of growing GM crops on a large scale has sparked
various concerns, specifically those regarding ecosystems with GMO
strains. According to scientists, these strains have the potential to change
agriculture in a negative way.
Futureofworking.com
INTRODUCTION
Genetic modification (GM) is the area of biotechnology which concerns itself
with the manipulation of the genetic material in living organisms, enabling
them to perform specific functions.1,2 The earliest concept of modification for
domestication and consumption of plants dates back ∼10,000 years where
human ancestors practiced “selective breeding” and “artificial selection” – the
Darwinian-coined terms broadly referring to selection of parent organisms
having desirable traits (eg: hardier stems) and breeding them for propagating
their traits. The most dramatic alteration of plant genetics using these methods
occurred through artificial selection of corn – from a weedy grass possessing
tiny ears and few kernels (teosinte; earliest recorded growth: central Balsas
river valley, southern Mexico 6300 years ago) to the current cultivars of edible
corn and maize plants (Doebley et al., 2016, Fig 1). The use of similar
techniques has also been reported to derive current variants of apples,
broccoli and bananas different from their ancestral plant forms which are
vastly desirable for human consumption.3
FIGURE 1. The evolution of modern corn/maize (top) from teosinte plants
(bottom) by repetitive selective breeding over several generations.
[Sources: 50 (top figure),51 (bottom figure)].
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The developments leading to modern genetic modification took place in 1946
where scientists first discovered that genetic material was transferable
between different species. This was followed by DNA double helical structure
discovery and conception of the central dogma – the transcription of DNA to
RNA and subsequent translation into proteins – by Watson and Crick in 1954.
Consequently, a series of breakthrough experiments by Boyer and Cohen in
1973, which involved “cutting and pasting” DNA between different species
using restriction endonucleases and DNA ligase – “molecular scissors and
glue” (Rangel, 2016) successfully engineered the world's first GM organism. In
agriculture, the first GM plants – antibiotic resistant tobacco and petunia –
were successfully created in 1983 by three independent research groups. In
1990, China became the first country to commercialise GM tobacco for virus
resistance. In 1994, the Flavr Savr tomato (Calgene, USA) became the first
ever Food and Drug Administration (FDA) approved GM plant for human
consumption. This tomato was genetically modified by antisense technology to
interfere with polygalacturonase enzyme production, consequently causing
delayed ripening and resistance to rot.4 Since then, several transgenic crops
received approvals for large scale human production in 1995 and 1996. Initial
FDA-approved plants included corn/maize, cotton and potatoes (Bacillus
thuringiensis (Bt) gene modification, Ciba-Geigy and Monsanto) canola
(Calgene: increased oil production), cotton (Calgene: bromoxynil resistance)
and Roundup Ready soybeans (Monsanto: glyphosate resistance),4 Fig 2).
Currently, the GM crop pipeline has expanded to cover other fruits, vegetables
and cereals such as lettuce, strawberries, eggplant, sugarcane, rice, wheat,
carrots etc. with planned uses to increase vaccine bioproduction, nutrients in
animal feed as well as confer salinity and drought resistant traits for plant
growth in unfavourable climates and environment.4,2
FIGURE 2. A timeline of events leading to the current GM crop era.
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Since their commercialisation, GM crops have been beneficial to both
economy and the environment. The global food crop yield (1996–2013) has
increased by > 370 million tonnes over a relatively small acreage
area.2 Furthermore, GM crops have been recorded to reduce environmental
and ecological impacts, leading to increases in species diversity. It is therefore
unsurprising that GM crops have been commended by agricultural scientists,
growers and most environmentalists worldwide.
Nevertheless, advancements in GM crops have raised significant questions of
their safety and efficacy. The GM seed industry has been plagued with
problems related to human health and insect resistance which have seriously
undermined their beneficial effects. Moreover, poor science communication by
seed companies, a significant lack of safety studies and current mistrust
regarding GMOs have only compounded problems. These have led many
countries, particularly the European Union and Middle East to implement
partial or full restrictions on GM crops. GM agriculture is now widely discussed
in both positive and negative frames, and currently serves as a hotbed of
debate in public and policymaking levels.
CHALLENGES IN COMMERCIAL AGRICULTURE
The agriculture industry has been valued at an estimated US$ 3.2 trillion
worldwide and accounts for a large share of the GDP and employment in
developing and underdeveloped nations.5 For instance: Agriculture contributes
only 1.4% towards the GDP and 1.62% of the workforce in US in comparison
with South Asian regions, where it contributes 18.6% towards the GDP and
50% of the workforce.6 However, despite employing nearly 1 in 5 people
worldwide (19% of the world's population),7 the agriculture industry is
projected to suffer significant global setbacks (population growth, pest
resistance and burden on natural resources) by 2050, which has been
elaborated further in this section.
Explosive Population Growth
The Food and Agricultural Organisation projects the global population to grow
to approximately 9.7 billion by 2050 – a near 50% increase from 2013 – and
further to an estimated 11bn by 2100. Current agricultural practices alone
cannot sustain the world population and eradicate malnutrition and hunger on
a global scale in the future. Indeed, the FAO also estimates that despite a
significant reduction in global hunger, 653 mn people will still be
undernourished in 2030.8 Additionally, Ray et al. and other studies depict the
top four global crops (soybean, maize, wheat and rice) are increasing at 1.0%,
0.9%, 1.6% and 1.3% per annum respectively– approximately 42%, 38%, 67%
and 55% lower than the required growth rate (2.4%/annum) to sustain the
global population in 2050.9 Compounded with other problems such as
improved nutritional standards in the burgeoning lower-middle class and
projected loss in arable land (from 0.242 ha/person in 2016 to 0.18 ha/person
in 2050)2 due to degradation and accelerated urbanization, rapid world
population expansion will increase demand for food resources.
Pests and Crop Diseases
Annual crop loss to pests alone account for 20–40% of the global crop losses.
In terms of economic value, tackling crop diseases and epidemics and
invasive insect problem costs the agriculture industry approximately $290 mn
annually.8 Currently, major epidemics continue to plague commercial
agriculture. It has been projected that crop disease and pest incidences are
expanding in a poleward direction (2.7 km annually),10 indicated by coffee leaf
rust and wheat rust outbreaks in Central America. These incidences have
largely been attributed to an amalgamation of globalisation leading to
increased plant, pest and disease movement, increase in disease vectors,
climate change and global warming.8
https://www.tandfonline.com/doi/full/10.1080/21645698.2017.1413522
While working for The Cooperative Wheat Research Production Program in Mexico in 1944, scientist
Norman Borlaug studied ways to minimize the loss of wheat production due to stem rust, an infectious
fungus. Borlaug developed simple techniques for cross-breeding, harvesting, and planting seeds in
order to produce unusually disease-resistant strains of wheat. The result was a striking growth in
wheat yields. By 1963, largely due to Borlaug's techniques, Mexico was producing six times as much
wheat per year as in the year before Borlaug's arrival. Borlaug took his new techniques for agriculture
to other countries with food supply problems, including India and Pakistan, similarly revolutionizing
their agricultural sectors. These agronomical innovations resulted in what has become known
worldwide as the Green Revolution, and earned Borlaug a Nobel Peace Prize in 1970.
Over the next three decades, geneticists developed techniques for extending Borlaug's work by
altering crops at the genetic level, resulting in what are known as GMOs, or genetically modified
organisms. The use of GMOs has radically shifted the prevailing ground rules of world food
production; for example, farmers in climates that once proved inhospitable to certain crops are now
able to produce abundant harvests of varieties of those crops that have been genetically engineered
to withstand the climate. The reach of GMOs extends even beyond food production, as they now
frequently feature in the development of medicines.
Nevertheless, despite the great promise of this technology to benefit human quality of life, recent
research has revealed potential dangers that GMOs may pose to the environment and human health.
Many organizations and governments concerned with these negative effects have raised a vocal
opposition to GMOs. Some countries have not only banned GMO production but also GMO research.
As evidenced by the escalating food costs that gave rise to the global food crisis of 2008, starvation
remains a pressing problem in many parts of the world. Starvation is as often a consequence of
inadequate food production as it is of inadequate distribution. GMOs, therefore, are as important a
topic of debate today as ever. How do you view this technology? A rich understanding of the debate
requires familiarity with the ongoing research, as well as the key points of both sides of the GMO
debate. In this Spotlight, we provide a broad range of resources to help you gain a deeper
understanding of the many sides of the GMO landscape.
www.nature.com
Cons
Because genetically engineering foods is a relatively new practice, little is
known about the long-term effects and safety.
There are many purported downsides, but the evidence varies, and the
main health issues associated with GMO foods are hotly debated.
Research is ongoing.
This section discusses the evidence for a range of drawbacks that people
often associate with GMO foods.
Allergic reactions
Some people believe that GMO foods have more potential to trigger allergic
reactions. This is because they may contain genes from an allergen — a
food that prompts an allergic reaction.
The World Health Organization (WHO) discourage genetic engineers from
using DNA from allergens unless they can prove that the gene itself does
not cause the problem.
It is worth noting that there have been no reports of allergic effects of any
GMO foods currently on the market.
Cancer
Some researchers believe that eating GMO foods can contribute to the
development of cancer. They argue that because the disease is caused by
mutations in DNA, it is dangerous to introduce new genes into the body.
The American Cancer Society (ACS) have said that there is no evidence
for this. However, they note that no evidence of harm is not the same as
proof of safety and that reaching a conclusion will require more research.
Antibacterial resistance
There is concern that genetic modification, which can boost a crop’s
resistance to disease or make it more tolerant to herbicides, could affect
the ability of people to defend against illness.
There is a small chance that the genes in food can transfer to cells the
body or bacteria in the gut. Some GMO plants contain genes that make
them resistant to certain antibiotics. This resistance could pass on to
humans.
There is growing concern globally that people are becoming increasingly
resistant to antibiotics. There is a chance that GMO foods could be
contributing to this crisis.
The WHO have said that the risk of gene transfer is low. As a precaution,
however, it has set guidelines for the manufacturers of GMO foods.
Outcrossing
Outcrossing refers to the risk of genes from certain GMO plants mixing with
those of conventional crops.
There have been reports of low levels of GMO crops approved as animal
feed or for industrial use being found in food meant for human
consumption.
www.medicalnewstoday.com