Examples of GM Food
Are these claims supported by evidence?
Let’s take a look into
some examples of GM
Example 1: GM maize
About 7% of the world‟s maize (sweet corn) production is
lost to a pest called the European corn borer.
The larvae live inside the maize stalk.
Pest control is not efficient. Large amounts of pesticides are
The cost of growing maize increases.
causes losses to
farmers the environment the economy
A gene extracted from a soil bacterium is inserted
The GM maize can produce a
protein called Bt protein.
When the corn borer larvae eat
this protein, their intestinal walls
are damaged, causing them to
die of starvation.
The cost is lowered, the Less maize is lost.
Less pesticide is used.
crop yield increases.
Consumers get better quality and more maize
Example 2: GM rice
GM rice has a higher crop yield (greater
weight of rice per plant).
Farmers, consumers, economy
Rice is the main carbohydrate source in many
GM rice increases food supply thus may
reduce food shortage.
People suffering from hunger or in poverty
(rice may be cheaper)
A new GM rice – golden rice,
– rich in pro-vitamin A (a precursor of vitamin A)
People in developing countries suffer from vitamin A
deficiency leading to blindness
Golden rice may solve the problem of vitamin A
deficiency in developing countries.
A protein in a new variety of GM rice (Bt rice) may
cause allergy in humans (NB: this is NOT “golden rice”)
Are GM foods safe enough?
GM foods are supposed to be assessed by each
different country before it is allowed onto the market
GM foods are usually tested for their toxicity and
whether or not they cause allergy
Approved GM foods are therefore not likely to cause
risks to human health
The first GM food was marketed only in 1994.
– Long term effects on human health cannot yet be
Laboratory animals don‟t live as long as humans do
Animal tests can‟t pick up small effects on intelligence
or personality (brain functions)
Trials for food safety of GM crops are often carried
out by the companies that have developed them, not
by independent researchers.
Some GM food have antibiotic-
resistant marker genes
The desirable gene may be transferred
WITH an antibiotic-resistance gene.
By testing the modified organisms with
antibiotics, scientists can tell whether the
desired gene has been successfully
inserted into the “new” organism.
Some GM food have antibiotic-
resistant marker genes…
What is the risk?
The marker genes may be transferred to
other pathogens which become resistant,
antibiotics will no longer be effective in
This may lead to development of “super
Does GM food really benefit farmers and
GM crops are mainly developed by a few large
The companies have patents on the GM crops genome
Do the farmers need to pay extra to buy GM
The cost may be higher because the seeds
are more expensive
Potential risks to the environment?
Genes from GM crops might escape, through pollen, to
weeds which are relatives of the crops.
i.e. the genes may escape into the wild.
GM crops may be toxic to some insects that eat them.
Dead or dying insects may be eaten by birds.
The birds may die because of the toxic effect.
This may lead to extinction of some species of
insects or birds.
All organisms are interrelated. Changes in one species
may have unpredictable consequences in other parts
of an ecosystem.
GM crops may grow and reproduce faster.
They may out-compete other plants in an ecosystem.
Do we have a right to alter ANY
Is genetic engineering
Is genetic engineering „playing