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Examples of GM Food. Are these claims supported by evidence ?. Let ’ s take a look into some examples of GM food!. 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.
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Examples of GM Food Are these claimssupported by evidence? Let’s take a look into some examples of GM food!
Example 1: GM maize About 7% of the world’s maize (sweet corn) production is lost to a pest called theEuropean corn borer. The larvae live inside the maize stalk. Pest control is not efficient. Large amounts of pesticides are used. The cost of growing maize increases.
causes losses to farmers the environment the economy
The GM maize can produce a protein called Bt protein. Bt protein When the corn borer larvae eat this protein, their intestinal walls are damaged, causing them to die of starvation. A gene extracted from a soil bacterium is inserted into maize
benefits The cost is lowered, the crop yield increases. Less pesticide is used. Less maize is lost. Consumers get better quality and more maize GM
Example 2: GM rice • GM rice has a higher crop yield (greater weight of rice per plant). • Who benefits? Farmers, consumers, economy
Rice is the maincarbohydrate source in many countries. • GM rice increases food supply thus may reduce food shortage. • Who benefits? People suffering from hunger or in poverty (rice maybe cheaper)
Golden rice • 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.
Are GM foods safe enough? Bad news! A protein in a new variety of GM rice (Bt rice) may cause allergy in humans (NB: this is NOT “golden rice”)
GM foods are supposed to be assessed by each different country before it is allowed onto the market there • 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
But….. • The first GM food was marketed only in 1994. • Long term effects on human health cannot yet be assessed. 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.
Moreover…. Some GM food have antibiotic-resistant marker genes Why? 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 treating diseases. This may lead to development of “super pests”
Does GM food really benefit farmers and consumers? GM crops are mainly developed by a few large biotechnology companies The companies have patents on the GM crops genome Do the farmers need to pay extra to buy GM seeds? 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.
Reduction in biodiversity • 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.
Ethical problems? • Do we have a right to alter ANY genetic material? • Is genetic engineering unnatural? • Is genetic engineering ‘playing God’?