Introducing GM - Notes for teachers

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Most adults will have heard of GM crops and food, and maybe the controversy that has surrounded them in the UK and Europe, but some pupils may not be so familiar.

These teaching tools aim to be as neutral as possible about this subject. However, a lot of the material you will find about GM online is polarised either pro-GM or against GM. We hope that the Gene Jury GM resources will help pupils appreciate that GM is neither universally good nor universally bad, but a more complex, grey area.

What is GM?
Genetic modification involves inserting a gene, or genes, from one organism into the genes of another. GM can also mean deleting a gene or genes from an organism. Every cell of the new organism then carries those new genes or deletions, and they will pass them on to to any offspring they have.

For example, the genes for human insulin have been inserted into a type of bacteria, this bacteria is then used to manufacture human insulin on a large scale. A gene for pest resistance found in another type of bacteria has been inserted into soybean plants, to help soybean crops resist insect attack. GM is a basic principle widely used in diverse ways.

Here are some GM facts

Graph o fGM use in agriculture worldwide

The graph (left) shows Worldwide cultivation areas with GM plants, 1996 - 2009, in millions of hectares.  (Source GMO compass website).

GM crops are used widely outside of the EU and their use is increasing rapidly. In 2009, 77% of the world's soybean crop was genetically modified. The world’s leading soybean producers are the United States, Brazil, Argentina, and China.

14 million farmers used GM crops in 2009, 13 million of them in developing countries.

GM foods are widely eaten around the world. GM foods from other countries routinely enter the UK food chain. For example, glucose syrup is often made from GM maize and imported to the UK, where it is used to make a lot of the cakes, biscuits, soft drinks, sweets and ice cream that we eat.

There are few GM crops that are licensed to be grown in the UK, GM maize, is grown here, but presently there are lots of restrictions made on those growing it.

Each year, European countries import approximately 40 million tonnes of soy material (much of it GM), mostly for use as cattle, pig, and chicken feed.

Many food additives used in the UK, such as citric acid, food colouring, xanthan thickeners and vitamin C, are routinely manufactured by GM bacteria. GM Soybeans are also used to produce many food additives.

GM organisms are patented by the companies that paid for them to be created. Patenting is a type of copyright that means other people are not allowed to make copies, this means that if you are a farmer growing a GM crop, you are not allowed to save seed from one year to the next, as is traditional. If you are caught saving seed the company has a right to sue you.

GM crops often have higher yields under the right conditions, allowing a farmer to harvest more from the same area of land.

The food safety tests are considerably more rigorous for GM food than for non-GM food.

GM plants that kill their insect pests may also kill or damage other insects living locally, such as bees.

Some GM crops need less herbicide or pesticide sprayed on them than traditional varieties. This should benefit the environment.

GM techniques are often compared with traditional breeding techniques used routinely on farms. Both techniques involve modifying the genes of an organism for agricultural benefit. Traditional breeding, however, does not involve introducing genes from one species to another (GM does). However, GM allows introduction only of the gene of interest, while traditional breeding incidentally selects for neighbouring genes along with desired ones.

GM animals with human genes inserted are used to produce therapeutic proteins which can, for example, be harvested from milk or eggs.

Genetic modifications are routinely made in research labs and underpin a vast amount of research and development for example, in biotechnology, medical research (such as sequencing the human genome) and forensic DNA analysis.

Lots of things can and have been genetically modified, including:

  • GM bacteria to produce insulin for diabetics
  • GM cotton for clothes,
  • GM mice that may help us understand serious disease
  • GM flowers in bouquets and for growing in the garden.

All of these GM organisms are used in the UK