Genetic engineering

Overview

Click on the links above for teaching schemes, activities and web links and other resources related to this topic.

Introduction
This is a relatively short topic, and any potential applications for humans will probably have been dealt with in the sections on Medical Ethics or Genetic Diseases.

It provides a good opportunity to develop students' skills in making an argument based on evidence. The topic includes decision making and how decisions can be taken when information on risk is so unclear. It is also the vehicle for the introduction of the Science Explanation - the interdependence of species.

Many students initially seem to take their food for granted and to see price as the over-riding criterion for choice.

The web links on this site provide useful resources. One of the best balanced sources of information is the John Innes Centre. See the web links section of this topic for the URL.

A suggested route through the topic

1 Topical
A good way to start could be provided by a current media story. The refusal of GM food aid by some African countries in 2002/03 or the trade war between the US and EU over labeling of GM are examples.

• Get students to debate the issue briefly in small groups, asking them to identify the arguments and to write a list of questions they would need answered in order to make up their own minds. Record these questions and refer back to them later in the topic.

2 Agriculture and the ecosystem
Many students need an introduction to the basic idea of agriculture: the manipulation of plants, animals and their environment to suit human needs. Bring in the interdependence of species.

• Use a set of statistics showing how many people a field of given size might have fed in 1066, 1600, 1800, 1900 and 2000. The same point could be made by comparing world population over the centuries.
• Show a set of statistics with the changes in farming in Britain since World War Two.
• Ask for suggestions on how this improvement of yields has been achieved. Discuss some of the technologies involved: mainly breeding and the agrochemical industry.
• Review the idea of a food chain and the interdependence of species, perhaps linked to a short article on the decline of a British bird due to modern farming methods.
• Discuss the extent to which modern farming pre-GM is "natural".

3 A new Technology and its Applications

• Most groups will need formal teaching of how GM is actually done, otherwise they can easily develop misconceptions that suggest a far more precise and controlled process than is yet available.
• Give examples of a few GM characteristics and explain why they are of benefit.
• You could explore social influences on science by looking at the claims made for the potential benefits of GM crops. Then present the statistics showing which characteristics have in fact been most widely used. Who is determining the research priorities and why? Who is funding research into characteristics which might help improve food supply and nutrition in low income countries?

4 The risks of GM
There is so much partisan information about GM, often exaggerated, it is really important that students analyse any information carefully. Technical effects, both good and bad on consumers and on the ecosystem need to be distinguished from economic ones. It is important to be clear about which groups in society are expected to benefit and which groups might carry the risks.

• Use topical articles or information from pressure groups such as Friends of the Earth and ask groups to identify the arguments both for and against GM crops.
• Get them to analyse the articles to find how evidence is used to support the argument.
• Do the exercise which requires students in small groups to match evidence to argument.

5 Decision making
At this stage refer back to the topical issue if you started with that. They should now be able to answer many of the questions they posed. Alternatively you can introduce a topical issue now.
Get students, in small groups, to develop a point of view on the issue and remind them that they must have evidence to support it. The opinions can then be discussed in the whole class.

The British government is currently (May 2003) embarking on a consultation exercise. The results of this exercise would also be a good focus for an analysis of decision-making.

6 GM animals
It has been suggested here that GM animals are treated separately because, to date, the main uses are medical, not agricultural. Apart from reminding students about the different uses you could choose to focus in more detail on just one application, depending on which aspects of the specification you felt needed reinforcement. Any of these involve decision making.

A discussion on whether xenotransplantation is safe would provide a useful review of risk, medical ethics and immunity.

The rise in the use of animals in medical research thanks to the contributions made by GM animals to an understanding of genetics could form the basis of a debate on animal testing if you have not covered this earlier. It will also remind students that a high proportion of animals are used for basic research, not just for testing medicines.

The use of GM salmon in fish farms would review the interdependence of species.