2. Objectives:
Define Genetically Modified
Organisms & Biodiversity
Identify threats to Biodiversity
Enumerate advantages &
disadvantages of GMO
Cite examples of GMO
3.
4.
5.
6.
7.
8.
9. Definition of Terms
Genetically Modified Organisms
• Genetically Modified Organisms are the ones in
which the genetic material (DNA) has been
altered in such a way as to get the required
quality. This technology is often called „gene
technology‟, or „recombinant DNA technology‟ or
„genetic engineering‟ and the resulting organism
is said to be „genetically modified‟, „genetically
engineered‟ or „transgenic’ (Sabha, 2009).
10. Definition of Terms
Biological Diversity
• Biological diversity as a concept refers to the
variety and variability of living organisms
(Millenium Ecosystem Assesment, 2005).
18. Threats to Diversity
Further signs of stress in the
global biodiversity is that the
population size or range (or both)
of the majority of species across
a range of taxonomic groups is
declining (MEA 2005).
Currently, estimated species
extinction rates are 1,000 times
higher than background rates
typical of the planet‟s history
(MEA 2005; Lövei 2007). A total
of 10–30% of mammal, bird, and
amphibian species are currently
threatened with extinction
(Secretariat CBD 2006).
19.
20. Advantages of GMO
Increase in agricultural activity
• This would be an important benefit, in a world in which
demand on lands is increasing. Commercial aquaculture
also utilises GM technology, to increase species growth
and adaptability. (Royal Society of Canada, 2001)
21. Advantages of GMO
Carbon-storage and climate change
• Benefits may accrue from the use of GM trees. As
disputes concerning the value of “carbon sequestration”
within the climate change analysis have been generally
resolved, the use of these trees is generally
expected, and some has already begun. Recent
research by WWF shows that since 1988 there have
been 184 GM tree field trials globally (Asante-
Owusu, 1999).
22. Advantages of GMO
Minimisation of pesticide use
• Here also, the environmental benefit can be
significant, given the role of agricultural pesticides in
species extinctions, and in the contamination of critical
ecosystems.
23. Advantages of GMO
“Edible vaccines”
• It has been noted that diarrhoea caused by bacteria is one of
the leading sources of infant mortality, particularly in the
developing world, where obtaining injections in time may be
difficult. Recent animal studies involving transgenic bananas
and tomatoes, which produce vaccines against cholera or to
address specific disease agents responsible for many
prevalent kinds of diarrhoea, are producing encouraging early
results. In future, such food vaccines might also be able to
suppress auto-immunity (a condition in which the body‟s
defences mistakenly attack normal uninfected tissue).
(Arntzen, 1995)
24. Advantages of GMO
Intentionally “invasive” uses
• GM insects have been developed, with a variety of
objectives, such as to reduce populations of insect pests
whose damage to agricultural crops is particularly
high, and to inhibit negative traits in “wild” insects
(including the trait which allows anopheles mosquitoes
to host the malaria parasite.) (Zitner,2001)
25. DISadvantages of GMO
Genetic contamination/interbreeding
• GMOs could possibly interbreed with other sexually
compatible species within the area in which the GMOs
were introduced. Some experiments have shown that
the rate of cross-pollination between conventional and
GM varieties of potatoes are generally low and become
negligible when the separation distance exceeds 10
metres (Rogers, 1995).
26. DISadvantages of GMO
Genetic contamination/interbreeding
• By contrast, Danish field trials have shown that oilseed
rape modified for herbicide tolerance can easily cross
with wild Brassica species such as wild mustard
(Chevre, 1997). Consequently, cross-pollination
between GM and non-GM oil seed rape has been
detected at distances of up to 2 km.
27. DISadvantages of GMOfa
Competition with natural species
• One trait that is often promoted by GM crop developers
is increasing productivity through faster growth. Fast
maturation, however, can serve as a significant
competitive advantage, which might allow an organism
to become invasive (spread into new habitats and cause
ecological or economic damage). Even where there is
no likelihood that a given GM species will interbreed
with wild species in the area, it may out-
compete, forcing them into decline and possible
extinction.
28. DISadvantages of GMO
Increased selection pressure on target and non-target
organisms
• Forty years of empirical evidence from the
U.S., Japan, Central America and China demonstrates
that the use of the pesticides consisting of Bt toxin (a
naturally occurring pesticide, now incorporated in
numerous crops for resistance to certain insects) has
allowed some agricultural pests (such as the diamond
back moth Plutella xylostella) to evolve distinct toxin
resistant populations. (Tabashnik, 1994)
29. DISadvantages of GMO
Impossibility of follow-up
• One example involves the introduction of barn owls in the
Seychelles, to control the population of inadvertently
introduced European rats. The owls (natural predators of
the rat species in their native surroundings) found other, in
some cases endangered, species much easier to catch.
They were able to out-compete native species that preyed
on these animals, and eventually represented a much more
serious threat to the island ecosystem than the rats they
were imported to control. (FAO,1993)
30. DISadvantages of GMO
Invasive Alien Species
One way to assess the potential invasiveness of GM
crops is through the IPPC‟s (International Plant
Protection Convention) Invasive Species and Pest
Management risk criteria:
• Changes in adaptive characteristics (that may
increase the potential for establishment and spread);
• Adverse effects of gene transfer/flow (that may result
in the establishment and spread of pests, or the
emergence of new pests);
• Adverse effects on non-target organisms;
• Genotypic or phenotypic instability (that could result
in the establishment and spread of organisms with
new pest characteristics).
31.
32. Insect Resistance
• Crops that have insect resistance represented 16.2 per cent of
the global area planted in 2005 (James, 2005). They are often
known as Bt crops due to the protein genes that are introduced
into a plant following extraction from a bacterium known as
Bacillus thuringiensis. This bacterium is found naturally in
soil and has been used in organic agriculture for insecticide
preparations because it is toxic to specific groups of insects
(Prakesh, 2005). Bt kill insects with toxins called insecticidal
crystal proteins or delta endotoxins. Delta endotoxins
rapidly paralyze the insect‟s digestive system, so damage to
the plant stops soon after the insect is exposed to the toxin
(Colorado State University Extension, 2010).
34. Bt Eggplant
• Genes from the bacterium Bacillus thuringiensis has been
inserted into the DNA of the eggplant so that it produces a
protein called Cry1Ac, which is a toxin. Importantly, there are
no commercial food crops with this type of Bt gene. For
Cry1Ac, there is concern over its potential allergenicity.
Moreover, the Bt toxins in GE eggplant are specifically toxic to
Lepidoptera (butterflies and moths), but not all of these are
pests (Dr. Janet Cotter, 2011).
35. Bt Potato
• One of the most consequential potato plant pests is the potato
beetle (Leptinotarsa decemlineata), which often becomes
resistant to chemical insec-ticides. Modified potatoes carrying
gene Cry3A originating from bacteria Bacillus thuringiensis
were produced to control this beetle. This gene product is a
toxic protein formed in leaves of these plants; after ingestion
by a potato beetle, it passes on to its intestines and thus
causes the death of the pest
(Pribylova, Pavlik, Bartos, 2006).
36. GM Potato
• Potato plants resistant to increased soil salt levels were
produced by insertion of a gene for glyceralde-hyde-3-
phosphate-dehydrogenase (GPD) from oyster mushroom
(Pleurotus sajor-caju) into potato plant genome. The effect
of the protein was tested by culti-vation of potato plants in
sodium chloride containing soil. Whereas GPD-free potato
plants died in several days, transgenic plants exhibited a high
tolerance to the presence of salts (Jeong et al., 2001).
38. Biofortification
• It is the adding of essential nutrients, vitamins and metabolites
with plants during their growth and development, thereby
making these additives more readily available for
human/animal consumption.
• Recently it was divided into agronomic and genetic
fortification. The first one uses soil and spray fertilizers
enriched by individual essential elements (eg Fe, Zn and
Se). This approach has been adopted with success in Finland
for enrichment of crops by Se. On the other hand, the
genetic pcfortification present the possibility to enrich food
crops by selecting or breeding crop varieties, which
enhanced Se accumulation characteristics (Broadley, et.
al., 2006).
40. Golden Rice
• Originally, the scientists who developed the rice had expected grains to be
red due to the genes they had inserted. Rice grains were supposed to
generate red carotenoids, so-called lycopenes like those found in
tomatoes. The authors revealed in their study that the original genes of
the plant unexpectedly caused the lycopenes to be converted into yellow
carotenoids. The yellow color giving the rice its name (Golden Rice) was
the outcome of an unintended reaction, caused by interactions between
inserted genes and the genome of the plants (Schaub et al., 2005).
42. Golden Rice
The b-carotene in GR is as effective as pure b-carotene in oil and better
than that in spinach at providing vitamin A to children. A bowl of
approximately 100 to 150 g cooked GR (50 g dry weight) can provide
approximately 60% of the Chinese Recommended Nutrient Intake of
vitamin A for 6–8-y-old children (Guangwen Tang, Yuming Hu, Shi-an
Yin, Yin Wang, Gerard E Dallal, Michael A Grusak, and Robert M
Russell, 2012).
43. Control or Chaos?
Unwanted and uncontrollable spread of GM plants is a highly
visible process on a global scale. By the end of 2006, over 100 cases of
confirmed, unwanted contamination and 26 cases of illegal releases
were registered (mostly by civil society organisations). A total of 39
countries on five continents have been affected, almost twice the
number of countries that currently grow GM crops. In 2005, there were
seven documented cases of contamination and eight illegal releases. In
2006, the number of contamination cases more than doubled to 15.
Most prominently, two unapproved GM events were found in rice (a
herbicide-tolerant transgene from the USA and a Bt transgene from
China) – these were detected at the consumer level (in shipments
intended for human consumption). More problematic is the detection of
plants with GM traits that have not yet been commercialised.
44. • Due to their reproductive
Glofish biology, fish are relatively
simple to genetically
modify and have thus been
the main focus of GM
animal research, with more
modified species than all
other vertebrates
combined. One GM fish is
already commercially
available in the USA for
aquariums – the Glofish, a
Zebra danio modified to
produce a red fluorescent
protein.
45. Glofish • Transgenic zebrafish
contained the gene
(dsRed) coding for the red
fluorescent
protein, originally isolated
from the marine sponge
Discosoma striata.
• Their color is caused by
high concentration of red
fluorescent protein (RFP)
in fish muscle (Gond et.
Al., 2003).
46. AquAdvantage®
Salmon
• GM salmon that can reach adult size three times faster than their non-
GM relatives (IUCN The World Conservation Union).
47. AquAdvantage®
Salmon
• Escaped genetically engineered salmon are likely to
compete with wild fish, including endangered Atlantic
salmon, for habitat, food, and mates (Ford JS and Myers
RA. 2008).
48. AquAdvantage®
Salmon
• Research published in the Proceedings of the National
Academy of Sciences found that the release of just 60
genetically engineered fish into a wild population of 60,000
could lead to the extinction of the wild population in less than
40 generations (Howard RD, DeWoody JA, Muir
WM., 2004).
49. AquAdvantage®
Salmon
• However, Aquabounty claimed that AAS will be grown as
sterile, all-female populations in land-based facilities with
redundant biological and physical containment.
• As a result, AquAdvantage® Salmon cannot escape or
reproduce in the wild and pose no threat to wild salmon
populations.
50. AquAdvantage® Salmon
• Six chemicals (folic acid, niacin, vitamin
B6, magnesium, phosphorus and zinc) are present in
genetically engineered salmon at values that differ by
more than 10 percent from conventional farmed
salmon, indicating potential food quality differences
among the two kinds of fish.
51. AquAdvantage® Salmon
• The omega 3/omega 6 ratio in genetically engineered
salmon is more than 12 percent less than in conventional
farmed salmon, a difference that could be of interest to
seafood consumers looking to maximize omega 3 levels
in their own diets.
52. AquAdvantage® Salmon
• Data indicate there may be higher levels of allergy-
producing compounds in genetically engineered
salmon, meaning the fish may pose a greater food
allergy threat. Given the limited sample sizes, more study
is needed to definitively rule out this concern.
53. AquAdvantage® Salmon
• Levels of Insulin-like Growth Hormone (IGF-1) are
elevated in genetically engineered salmon compared to
conventional farmed salmon. The long-term health
impacts of this are unclear, but IGF-1 is a known
carcinogen.
54. Synthesis
In general, Biodiversity cannot fully be replace by
Genetically Modified Organisms due to the
following reasons: firstly, GMO itself may causes
alteration to ecological balance; second, there is no
any supportive studies which can prove that it may
actually sustain life, the way that the natural
environment can; and lastly, there is no perfect
assurance that GMO can actually exist for a
lifetime without a failure with its function.