NAME
NAME : NONDUMISO C. SITHOLE
STUDENT NO. : 21539932
QUALIFICATION : ND BIOTECHNOLOGY
FOOD MICROBIOLOGY
ASSIGNMENT
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Table of Contents
Introduction …………………………………………………………………………………………………………….. 2-3
abstract ………………………………………………………………………………………………………………….. 2
my opinion …………………………………………………………………………………………………………….. 3
Body ………………………………………………………………………………………………………………………. 4-8
conclusion ………………………………………………………………………………………………………………. 9
References ……………………………………………………………………………………………………………….. 10
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Introduction
Abstract
Genetic modification is a special set of gene technology that alters the genetic machinery of
such living organisms as animals, plants or microorganisms. Combining genes from different
organisms is known as recombinant DNA technology and the resulting organism is said to be
‘Genetically modified (GM)’, ‘Genetically engineered’ or ‘Transgenic’. The food made by
genetic modification is called genetically modified food.
Genetically modified food is food produced from any crop or animal that has been genetically
altered during its production using the modern techniques of gene technology. Modification
usually involve changing one gene of the 30 000-50 000 odd genes that make up an organism.
The principal transgenic crops grown commercially in field are herbicide and insecticide
resistant soybeans, corn, cotton and canola. Other crops grown commercially and/or field-
tested are sweet potato resistant to a virus that could destroy most of the African harvest, rice
with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries and
a variety of plants that are able to survive weather extremes.
There are bananas that produce human vaccines against infectious diseases such as hepatitis B,
fish that mature more quickly, fruit and nut trees that yield years earlier and plants that produce
new plastics with unique properties. Technologies for genetically modifying foods offer
dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all
new technologies, they also pose some risks, both known and unknown. Controversies and
public concern surrounding GM foods and crops commonly focus on human and environmental
safety, labelling and consumer choice, intellectual property rights, ethics, food security,
poverty reduction and environmental conservation.
Introduction.
Genetically modified foods has become a major concern and have caused controversy
regarding both their health and environmental effects. Regardless of their effect I find Genetic
modification helpful.
Scientists first discovered in 1946 that DNA can be transferred between organisms (Allison,
2015). It is now known that there are several mechanisms for DNA transfer and that these occur
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in nature on a large scale, for example, it is a major mechanism for antibiotic resistance in
pathogenic bacteria. The first genetically modified (GM) plant was produced in 1983, using an
antibiotic-resistant tobacco plant. China was the first country to commercialize a transgenic
crop in the early 1990s with the introduction of virus resistant tobacco. In 1994, the transgenic
‘Flavour Saver tomato’ was approved by the Food and Drug Administration (FDA) for
marketing in the USA. The modification allowed the tomato to delay ripening after picking.
Genetic modification involve taking genes and segments of DNA from one species, for
example fish and put them into another species for example tomato. Genetic modification
provides a set of techniques to cut DNA either randomly or at a number of specific sites. Once
isolated, one can study the different segments of DNA, multiply them and splice them next to
any other DNA of another cell or organism. Genetic modification makes it possible to break
through the species barrier and to shuffle information between completely unrelated species.
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Body
At present there are several GM crops used as food sources. As of now there are no GM animals
approved for use as food, but a GM salmon has been proposed for FDA approval. In instances,
the product is directly consumed as food, but in most of the cases, crops that have been
genetically modified are sold as commodities, which are further processed into food
ingredients. The following are some examples of GM food:
GM maize
Two lines of Chardon LL herbicide-resistant GM maize expressing the gene of
phosphinothricin acetyltransferase before and after ensiling showed significant differences in
fat and carbohydrate contents compared with non-GM maize and were therefore substantially
different come.
Figure 1, GM maize: geneliteracyproject.org.
GM soybeans
To make soybeans herbicide resistant, the gene of 5-enolpyruvylshikimate-3-phosphate
synthase from Agrobacterium was used. Safety tests claim the GM variety to be “substantially
equivalent” to conventional soybeans (Beagle, 2016). The same was claimed for GTS
(glyphosate-resistant soybeans) sprayed with this herbicide (Brake, 2015). However, several
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significant differences between the GM and control lines were recorded (Ballan, 2017) and the
study showed statistically significant changes in the contents of genistein (isoflavone) with
significant importance for health (Bernstein, 2015) and increased content in trypsin inhibitor.
Figure 2, GM soybeans: geneliteracyproject.org
GM potatoes
There were no improvements in the protein content or amino acid profile of GM potatoes
(Allison, 2015). In a short feeding study to establish the safety of GM potatoes expressing the
soybean glycinin gene, rats were daily force-fed with 2 g of GM or control potatoes/kg body
weight (Berberich, 2016). No differences in growth, feed intake, blood cell count and
composition and organ weights between the groups were found.
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Figure 3, GM potatoes: geneliteracyproject.org
GM rice
The kind that expresses soybean glycinin gene (40–50 mg glycinin/g protein) was developed
(Brake, 2015) and was claimed to contain 20 % more protein. However, the increased protein
content was found probably due to a decrease in moisture rather than true increase in protein
Figure 4, GM rice : geneliteracyproject.org
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Before we think of having GM foods it is very important to know about is advantages and
disadvantages especially with respect to its safety. These foods are made by inserting genes of
other species into their DNA. Though this kind of genetic modification is used both in plants
and animals, it is found more commonly in the former than in the latter. Experts are working
on developing foods that have the ability to alleviate certain disorders and diseases. Though
researchers and the manufacturers make sure that there are various advantages of consuming
these foods, a fair bit of the population is entirely against them.
GM foods are useful in controlling the occurrence of certain diseases. By modifying the DNA
system of these foods, the properties causing allergies are eliminated successfully. These foods
grow faster than the foods that are grown traditionally. Probably because of this, the increased
productivity provides the population with more food. Moreover these foods are a boon in places
which experience frequent droughts, or where the soil is incompetent for agriculture. At times,
genetically engineered food crops can be grown at places with unfavourable climatic conditions
too.
A normal crop can grow only in specific season or under some favourable climatic conditions.
Though the seeds for such foods are quite expensive, their cost of production is reported to be
less than that of the traditional crops due to the natural resistance towards pests and insects.
This reduces the necessity of exposing GM crops to harmful pesticides and insecticides,
making these foods free from chemicals and environment friendly as well. Genetically
engineered foods are reported to be high in nutrients and contain more minerals and vitamins
than those found in traditionally grown foods. Other than this, these foods are known to taste
better. Another reason for people opting for genetically engineered foods is that they have an
increased shelf life and hence there is less fear of foods getting spoiled quickly.
The biggest threat caused by GM foods is that they can have harmful effects on the human
body. It is believed that consumption of these genetically engineered foods can cause the
development of diseases which are immune to antibiotics. Besides, as these foods are new
inventions, not much is known about their long term effects on human beings. As the health
effects are unknown, many people prefer to stay away from these foods. Manufacturers do not
mention on the label that foods are developed by genetic manipulation because they think that
this would affect their business, which is not a good practice.
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Many religious and cultural communities are against such foods because they see it as an
unnatural way of producing foods. Many people are also not comfortable with the idea of
transferring animal genes into plants and vice versa. Also, this cross-pollination method can
cause damage to other organisms that thrive in the environment. Experts are also of the opinion
that with the increase of such foods, developing countries would start depending more on
industrial countries because it is likely that the food production would be controlled by them
in the time to come.
The GM foods have the potential to solve many of the world’s hunger and malnutrition
problems, and to help protect and preserve the environment by increasing yield and reducing
reliance upon synthetic pesticides and herbicides. Challenges ahead lie in many areas viz.
safety testing, regulation, policies and food labelling. Many people feel that genetic engineering
is the inevitable wave of the future and that we cannot afford to ignore a technology that has
such enormous potential benefits.
Future also envisages that applications of GMOs are diverse and include drugs in food, bananas
that produce human vaccines against infectious diseases such as Hepatitis B (Bleagle 2016),
metabolically engineered fish that mature more quickly, fruit and nut trees that yield years
earlier, foods no longer containing properties assth common intolerances, and plants that
produce new biodegradable plastics with unique properties (Allison,2015). While their
practicality or efficacy in commercial production has yet to be fully tested, the next decade
may see exponential increases in GM product development as researchers gain increasing
access to genomic resources that are applicable to organisms beyond the scope of individual
projects.
One has to agree that there are many opinions (Ballan, 2017) about scarce data on the potential
health risks of GM food crops, even though these should have been tested for and eliminated
before their introduction. Although it is argued that small differences between GM and non-
GM crops have little biological meaning, it is opined that most GM and parental line crops fall
short of the definition of substantial equivalence. In any case, we need novel methods and
concepts to probe into the compositional, nutritional, toxicological and metabolic differences
between GM and conventional crops and into the safety of the genetic techniques used in
developing GM crops if we want to put this technology on a proper scientific foundation and
allay the fears of the general public.
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Considerable effort need to be directed towards understanding people’s attitudes towards this
gene technology. At the same time it is imperative to note the lack of trust in institutions and
institutional activities regarding GMOs and the public perceive that institutions have failed to
take account of the actual concerns of the public as part of their risk management activities
Conclusion
Genetically modified foods have the potential to solve many of the world’s hunger and
malnutrition problems, and to help protect and preserve the environment by increasing yield
and reducing reliance upon chemical pesticides and herbicides. Yet there are many challenges
ahead, especially in the areas of safety testing, regulation, international policy and food
labelling. Many people feel that genetic engineering is the inevitable wave of the future and
that we cannot afford to ignore a technology that has such enormous potential benefits.
However, we must proceed with caution to avoid causing unintended harm to human health
and the environment.
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References
Allison S, Palma PM. Commercialization of transgenic plants: potential ecological
risks. BioScience. 2015;47:86–96. doi: 10.2307/1313019.
Ballari VR, Martin A, Gowda LR (2017) Detection and identification of genetically modified
EE-1 brinjal (Solanum melongena) by single, multiplex and SYBR® real-time PCR. J Sci Food
Agric. doi:10.1002/jsfa.5764, Published online 22 June 2017.
Beagle JM, Apgar GA, Jones KL, Griswold KE, Radcliffe JS, Qiu X, Lightfoot DA, Iqbal MJ.
The digestive fate of Escherichia coli glutamate dehydrogenase deoxyribonucleic acid from
transgenic corn in diets fed to weanling pigs. J Anim Sci. 2016;84(3):597–607.
Berberich SA, Ream JE, Jackson TL, Wood R, Stipanovic R, Harvey P, Patzer S, Fuchs RL.
The composition of insect-protected cottonseed is equivalent to that of conventional
cottonseed. J Agric Food Chem. 2016;44:365–371. doi: 10.1021/jf950304i.
Bernstein IL, Bernstein JA, Miller M, Tierzieva S, Bernstein DI, Lummus Z, Selgrade MK,
Doerfler DL, Seligy VL. Immune responses in farm workers after exposure to Bacillus
thuringiensis pesticides. Environ Health Perspect. 2015;107:575–582. doi:
10.1289/ehp.99107575
Brake J, Vlachos D. Evaluation of transgenic Event 176 “Bt” corn in broiler chicken. Poult
Sci. 2015;77:648–653.
Brian H. Unintended effects of Bt crops. World Watch. 2014;12:9–10.
