No technology since the power of the atom was unleashed has caused as much debate or as much concern as that of genetic engineering applied to food.

Our ability to alter the genetic blueprint of animals and plants is in the process of changing many aspects of science and medicine. Many people see this as beneficial.

But what about genetically-modified food? Do we want to eat such food? And just how has the food been modified?

When considering genetic engineering it should be remembered that almost every living thing man exploits has been genetically modified in a major way.

Prof Ray Baker, Science Council: Food on shelves is absolutely safe

The crops we use for food, the animals we eat as well as our pets and the plants in our gardens are radically different from those that existed in a so-called natural state.

Thousands of years of selective breeding have improved the food yield of crops, the milk production of cows, the quantity of meat on cattle and the sizes and colours of our flowers and dogs.

Without this programme of genetic modification modern life, with the high levels of population in the developed world, would be impossible as we know it. Mankind_s ingenuity and scientific knowledge feeds the world.

It is curious then, that many regard as dangerous the more efficient and knowledgeable way to breed animals and plants that uses the modern techniques of genetic engineering. It has been said that we are at the start of a new age of 'Frankenfood.' Are they right?

Yes and no

Scientists have ability to isolate and modify genes

The genetic developments of recent years, the ability to isolate, move and modify genes, is a true revolution. For the first time in our history we have the ability to manipulate the very blueprint of any living organism. We can take genes from fish that make them resistant to cold and insert them into a strawberry that will then grow better in cold conditions.

We can make wheat with more gluten that will make better bread and we can make tomatoes that keep their fresh-picked texture longer.

Critics of this work say that modern genetic engineering is not an extension of the traditional methods of breeding. Never in the past, they say, have we had the ability to transplant genes between widely different species, human genes into pigs for example.

Few would deny the benefits of modern genetic engineering. The use of genetically modified bacteria to produce drugs such as insulin has been a revolution in medicine and saved the lives of millions.

But do we need genetically modified food?

Genetic food already here

It is already here. The chances are that today you have already eaten a genetically modified foodstuff or a food that was made with a modified organism. Much Soya, found in many foods, is modified and much bread is nowadays produced with a genetically modified yeast.

All the indications are that these foods are harmless.

Most of the worries about engineered foods are not about the right things. Concerns about interfering with God's plan are a vague and ill-focused objection. God's plan, if you believe in such a thing, has been interfered with ever since the beginnings of agriculture 10,000 years ago.

But the question remains, do we need genetically modified food? Take corn as an example.

Some strains of corn have been genetically modified to protect it against insect pests. A gene has been inserted that produces a chemical that kills specific pests.

This allows farmers to reduce their use of pesticides, which can cause problems of their own.

Many studies have shown that corn that has been genetically altered to make it resistant to certain insect pests is no different in composition or nutritional quality than other commercially available corn varieties, and that it is suitable for food use.

Some crops, such as soya, have had a gene added to them to increase their resistance to pesticides so that farmers can use pesticides more efficiently.

But the fact that in some cases the same company that produces the modified soya seeds also produces the pesticide has led to allegations of corporate manipulation of food markets.

And this is one of the chief fears about such foods. That they are a market-driven juggernaut oblivious to concerns wider than profit. Many believe that the genetic engineering lobby has been just a bit too complacent about safety.

The key question is; when we change the genetic structure of a plant or an animal, do we know enough about what we are doing to be sure of safety. Life is complex and has an unfailing capacity to surprise.

We have a lot to thank the Green revolution for but we must remember evolution's ability to frustrate human desires.

Will the new genetic agricultural revolution mimic the disasters of the industrial age?