Genetically modified foods will soon affect ALL our lives

[Guest guest]

Genetically modified foods will soon affect all our lives

 

Genetically-modified (GM) food has become a major health and

environmental issue in the UK. It has sharply divided opinion,

between those who believe the new technology will greatly enhance

our lives and those who fear it will prove a scientific " advance "

too far.

Below BBC News Online answers some of the key questions.

 

What is GM food?

How new is it?

When was it invented?

How does the technology work?

What are the potential health risks?

Are there health benefits?

Can we trust our food?

What are the green issues?

How do I know what I am eating?

Who controls GM food?

 

 

What is GM food?

 

Genetically-modified (GM) food is produced from plants or animals

which have had their genes changed in the laboratory by scientists.

 

 

All living organisms have genes written in their DNA. They are the

chemical instructions for building and maintaining life. By

modifying the genes, scientists can alter the characteristics of an

organism.

 

We might, for examples, want to boost yields, increase muscle bulk

and make our crops and farm animals resistant to disease. Genetic

engineering holds out these possibilities.

 

However, the technology is in its infancy. Very few food crops have

been gene-altered using the new techniques, and there are no

foodstuffs on sale in the UK made from GM animals.

 

And none of the GM crops currently being commercially grown around

the world contain genes transferred from animals or humans.

 

Some will argue that this new technology is " unnatural " . Others will

point to the commonality that exists between species - from bugs and

worms to monkeys and humans, we already share many of the same genes.

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How does this technology differ from what went before?

 

Farmers have been engaged in what we might term " traditional

genetics " for thousands of years. They have long understood that

like begets like, favouring the seed from plants with the most

desirable characteristics.

 

New plant types have also arisen by cross-breeding closely-related

species. This is how we got oil seed rape and bread wheat.

 

But way genes are passed from one generation to the next through

sexual reproduction is something of a lottery.

 

Scientists have tried to speed things up by exposing experimental

plants to chemicals and radiation. This has the effect of producing

hundreds of mutations among the genes. Some of these may be useful,

others will not and the plants will be discarded.

 

Genetic engineering, on the other hand, is more specific. It allows

scientists to select a single gene for a single characteristic and

transfer that stretch of DNA from one organism to another - even

between different species.

 

An example of genetic engineering is the FlavrSavr tomato developed

by Calgene. When tomatoes ripen, a gene is triggered to produce a

chemical that makes the fruit go soft and eventually rot.

 

Scientists have now modified the gene which has the effect

of " switching off " the chemical. As a result, the FlavrSavr tomato

softens more slowly, meaning it can stay longer on the vine to

develop a fuller taste. Its longer shelf life also reduces waste.

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When was GM food invented?

 

The first transgenic plant - a tobacco plant resistant to an

antibiotic - was created in 1983. It was another ten years before

the first commercialisation of a GM plant in the United States - a

delayed-ripening tomato - and another two years (1996) before a GM

product - tomato paste - hit UK supermarket shelves.

 

1996 was also the year that the EU approved the importation and use

of Monsanto's Roundup Ready soya beans in foods for people and feed

for animals. These beans have been modified to survive being sprayed

with the Roundup herbicide that is applied to a field to kill weeds.

 

This soya, together with GM maize, is now used in a variety of

processed foods on sale in UK shops. The products range from crisps

to pasta.

 

A genetically-engineered version of the milk-clotting enzyme

chymosin is also used in cheese-making.

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How does the technology work?

 

Scientists have developed a number of techniques for getting a

desired gene into a plant. One technique makes use of a soil

bacterium, Agrobacterium tumefaciens.

 

This microbe, dubbed the " first genetic engineer " , has evolved the

ability to insert stretches of DNA into plants. The bacterium does

this to make plants produce the particular chemicals it needs to

survive. Scientists get A. tumefaciens to deliver genes of their

choice.

 

Labs also use a technique called biolistics. This uses a gun to fire

the desired gene into a plant's cells. The " foreign DNA " is carried

on tiny pieces of gold. With luck, the plant will take up the DNA

and start to read out its instructions. Wheat and rice have been

modified in this way.

 

Another method relies on protoplasts. These are plant cells which

have had their tough walls removed. This gives the foreign DNA

easier access to the cell interior.

 

All these techniques depend on the remarkable fact that many plants

can be regenerated from single cells or small pieces of plant

tissue - as all gardeners who take cuttings know. This means a

successful modification can be multiplied very quickly.

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Why do some people think this technology may be harmful to human

health?

 

Critics argue that we do not know enough about the way genes operate

and interact to be sure of what the outcome of any modification will

be. They worry that the alterations could accidentally lead to

substances that are poisonous or trigger allergies.

 

The anti-GM lobby is critical of the use of DNA from plant viruses

and bacteria in the modification of crops - they fear this may also

somehow trigger disease.

 

They have objected to the use of antibiotic-resistant marker genes

in transgenic crops, which are included by scientists to test

whether or not their main modifications have been successfully

incorporated into a plant.

 

The critics argue the antibiotic-resistant genes could be passed to

the micro-organisms that make us ill. If this happens, we might not

have the necessary drugs to fight back.

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How do the genetic engineers counter these arguments?

 

They will tell you there is no evidence of any GM food on UK

supermarket shelves having caused any ill effects.

 

They make the point that very many of the conventional foodstuffs in

our supermarket have only got there after their non-GM, raw

ingredients have been treated to remove undesirable or toxic

substances - and that the regulatory structures that govern GM foods

are, in many ways, far stricter than for conventional products.

 

Genetic modification might result in the emergence of new allergens,

but so too can conventional plant breeding, they say. However, the

new technology holds out the possibility of engineering such

problems out of food.

 

The use of DNA from plant viruses and bacteria presents little risk -

precisely because we are not plants. Cauliflowers are naturally

infected with a virus that is commonly used in the laboratory for

modification purposes, and we eat millions of the vegetables with no

ill effects.

 

Furthermore, genetic modification allows us to improve not only the

flavour, texture and shelf-life of food but also its nutritional

value. We could boost the vitamin content of fruits and vegetables,

incorporate anti-cancer substances, and reduce our exposure to the

less healthy oils and fats.

 

Bioengineers have also given us a new word to describe plants that

have been altered to have medicinal properties - " nutraceuticals " .

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So can we trust the food we eat?

 

All food products, novel or otherwise, are subject to a system of

regulation which should ensure safety and consumer confidence.

 

These regulations set standards or thresholds that must be met.

Testing procedures are designed to pick up problems before products

get on to the market. When we get ill as a result of eating food, it

is usually because of poor practice somewhere along the line.

 

BSE/CJD is a very good example of this: the rendering and abattoir

industries adopted ineffective procedures and failed to remove

specified meat products from the human food chain.

 

Remember that we the consumers also have responsibilities. One of

the reasons food poisoning cases have risen dramatically in recent

years is because we have failed to store and prepare food properly

in our own kitchens.

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What are the environmental concerns with GM crops?

 

The green lobby fears that some of the genes engineered into crops

could " escape " and be transferred to other species where they might

have adverse effects.

 

In particular, they are worried about genes that confer herbicide

and insect resistance. They believe leakage of these genes could

result in the emergence of " superweeds " and in the disappearance of

familiar species of insects and birds as food chains become damaged.

 

They accuse the biotech companies of trying to " handcuff "

agriculture by attempting to tie farmers into deals where they have

little choice but to buy the GM seed and the designer chemicals to

go with it.

 

Some of the biodiversity issues will be directly tested in the large-

scale GM crop trials to be undertaken in the UK. It can be argued

that the British countryside is already a " sick " place, where

modern, intensive farming methods have inflicted immeasurable harm

on the natural balance of things. The big question is whether the

new technology will exacerbate the problems.

 

Bioengineers will argue that GM technology offers a chance to

recover the situation. They say GM crops will require fewer

chemicals that have low toxicity, are rapidly degraded and stay in

the soil rather than being washed into rivers.

 

They will do this whilst at the same time producing higher yields.

This could reduce pressure on those remaining uncultivated habitats.

 

Scientists are also investigating whether plants can be modified to

produce new plastics and biofuels that would be kinder to the

environment than the products based on oil.

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How do I know what I am eating?

 

The UK Government, together with industry, is attempting to produce

better labelling of food - so that consumers know precisely what

they are buying, be it in a supermarket or in a restaurant.

 

The current rules state that GM food has to be labelled

unless " neither protein or DNA resulting from genetic modification

are present " .

 

In plain terms, this means the following: if a crop was modified to

alter the composition of a food ingredient, for example starch or

oil, then the food will have to be labelled - GM DNA or protein will

quite clearly be present in the food.

 

If the crop was modified to protect it from, say, insect attack and

no GM DNA or protein is present in the extracted and purified starch

or oil, the food will not have to carry a label.

 

In this instance, the starch or oil would be chemically identical to

those products that were obtained from " conventional crops " . This is

known as the concept of " substantial equivalence " .

 

The GM labelling rules should satisfy those who wish to exercise a

choice based on any perceived health threat, real or imagined.

However, the idea of substantial equivalence means the rules will

not satisfy those who object to GM foods on ethical or religious

grounds.

 

They are still denied choice because there will be some foodstuffs

on sale without a label whose manufacture has involved genetic

modification at some stage in the production process.

 

In addition, all this presupposes that the tests used to

detect " foreign " DNA or protein are foolproof - some scientists

argue they are not.

 

This is one of the reasons why supermarkets are now going to sources

where the origin and purity of raw materials can be guaranteed.

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Where is GM food grown?

 

There are up to 500 small experimental sites in the UK, but all GM

food on sale in the UK has been grown aboard, much of it in the USA.

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Who is monitoring the safety of GM food?

 

There are European Union directives covering what are more generally

known as genetically-modified organisms (GMOs). In the UK

specifically, two committees offer advice to the government. They

are composed of university academics and industry experts. The

Advisory Committee on Releases into the Environment (ACRE) includes

an environmentalist and the Advisory Committee on Novel Foods and

Processes (ACNFP) has one consumer representative and an ethicist.

 

There are roles also for the Committee on Toxicity in Food, Consumer

Products and the Environment (COT), the Food Advisory Committee

(FAC) and the Health and Safety Executive (HSE). Any company that

brings a GM food to market will have had to pass several expert

committees - a process that takes many years.

 

The government has also promised a Food Standards Agency.

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This page only gives a brief account of some of the main points in

the GM food issue. For more in-depth information see some of the

dedicated sites in our links section.

[Guest guest]

There are so many people with health issues that could be solved by steering

away from GMO foods and inorganic foods. I stopped buying a lot of inorganic

produce some 8 months ago, gradually buying less and less until I am now

buying only organic where possible. I know it takes a little bit of effort

to source good organic foods but believe me it is so worth it in the end.

With organic you know that it does not contain any GMO's, it does not contain

pesticides, it does not contain growth hormones and it is good for you.

 

Thanks to a great deal of education from these groups, I learned very quickly

how to care for and nurture my body - long, happy life here I come.

 

Marianne

 

 

> Genetically modified foods will soon affect all our lives

>

> Genetically-modified (GM) food has become a major health and

> environmental issue in the UK. It has sharply divided opinion,

> between those who believe the new technology will greatly enhance

> our lives and those who fear it will prove a scientific " advance "

> too far.

> Below BBC News Online answers some of the key questions.

>