For once the government has got it right. In sanctioning the cultivation of genetically modified (GM) maize, it is allowing fact finally to triumph over fantasy.

But wait, you say. More than 80% of people disagree with the government’s decision, according to opinion polls. Surely they cannot all be wrong?

Oh yes they can. Before the 16th century most people believed the earth to be flat. Until the late 19th century the view that diseases such as cholera and malaria were caused by foul air prevailed. Even today 70% of Americans believe in miracles. Basing governmental policy on the ignorance of the majority is bad strategy.

Forget Frankenstein food: join me, instead, in simple biochemistry. The difference between GM maize and its unmodified counterpart is this: the GM variety contains an additional gene, that is to say a bit of “foreign” DNA. It also contains the protein made according to that gene’s instruction.

DNA and proteins are both large molecules. When we eat them, each is broken down to its constituent units in our intestine before being absorbed into the bloodstream.

There are just four different constituent units — called nucleosides — in DNA, and 20 constituent units of proteins (called amino acids). The four nucleosides of DNA and the 20 amino acids of proteins are the same in all organisms — plants and microbes, animals and humans.

Whether you choose to eat a banana or a camelia, the liver of a bat or the kidneys of a whale, the same four nucleosides and the same 20 amino acids will finish up in your blood. So it makes not a jot of difference that in GM maize less than 0.001% of the total DNA and protein is slightly different from that in conventional maize. The digested units are identical.

But wait. Isn’t it true that prior to degradation, proteins are occasionally able to elicit an immune response? Isn’t that how the oral polio vaccine works? Quite right, and immune responses underlie the allergic reactions that some people suffer when eating peanuts, for example. And it is possible that the aberrant protein in GM maize could set off such a reaction.

Theoretically. But millions of people have been consuming GM products on a daily basis throughout America, Argentina, Canada and China since 1996 — and not a single one has suffered an allergic reaction of this type.

How much bigger does a trial need to be to assure the doubters? A trial involving every one of the six billion people alive today?

So much for the health risks. What about the environmental consequences? This is precisely what recent studies, like that sponsored by the government, have set out to assess. Three types of GM crop were grown alongside unmodified counterparts at more than 200 sites over a three-year period: maize, beet and oilseed rape. The GM versions contained genes that make the plants resistant to a herbicide called glufosinate (not to be confused with atrazine, the herbicide which is being phased out across the European Union).

Glufosinate is a powerful weedkiller that destroys all plants to which it is exposed — except those that have been made resistant to it by genetic modification. Animals and humans are also unaffected by the herbicide.

GM crops can therefore be sprayed with glufosinate at earlier times during the growing season than would be possible with unmodified crops. The outcome of the studies was clear: in the case of GM beet and oilseed rape, contamination by weeds was down three-fold compared with unmodified beet or rape.

This is clearly good news for farmers. But it is bad news for the insects and birds that feed on weeds and their seeds — and it is for this reason that the government has decided not to recommend the commercial use of GM beet or oilseed rape at this time.

On the other hand, if the herbicide is used carefully, GM maize can be grown so as to encourage more weeds to develop. This is good news for butterflies and bees, but not a particularly attractive scenario for farmers. However, it is this combination of crop and herbicide that the government is to allow for commercial use.

So how important is it that GM technology is introduced onto European farms? Probably not very. Affluent nations like the UK can indulge in their particular choice of agriculture: organic, conventional or GM.

But in the Third World this is not an option. Organic farming is too expensive and conventional farming produces too low a yield. The yield from the production of sweet potato in Africa is six tonnes per hectare; the global average is 14 tonnes (and in China it is 18 tonnes).

What is the reason for such low yields? Partly of course it is the weather: long periods of drought. But more than 40% of crops are also lost annually because of over-growth by weeds and attack by viruses and insects. As a result, Africa needs to import more than 25% of its grain, which it can ill afford to do. Drought-resistant and pest-resistant GM crops would be a lifeline.

Nowhere are herbicide-resistant crops, coupled with the use of cheap weedkillers, needed more than in sub-Saharan Africa, where 40,000 people — half of them children — are dying from malnutrition daily. We should be helping them by developing and promoting the relevant GM crops, not hindering their salvation by unjustified criticism of the technology.

We should set an example of sense, not bias, and encourage Third World nations to accept GM technology as the most effective way forward — second only to the removal of their corrupt leaders who with one hand steal 90% of the financial aid provided to their countries, and with the other create murder and mayhem and raze to the ground the feeble crops that their starving people are trying to nurture. Now there’s a cause the anti-GM technology gang might like to espouse.

Charles Pasternak is the author of a book about genetics, Quest, The Essence of Humanity (Wiley). He is director of the Oxford International Biomedical Centre (www.oibc.org.uk)

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