Even textbooks rarely present both the pros and cons of genetic engineering - only the pros. Engineered insulin, for example, is portrayed as an unalloyed boon. It is - for most of those who use it. But a balanced analysis should mention the 10 per cent in whom it can cause serious mental changes - including loss of memory and concentration which can cause diabetic children to fail in school. To understand today's world, children also need to know that doctors were so beguiled by public relations blurbs about engineered insulin that many refused to believe diabetics who said engineered insulin changed them.
As a positive image what could be more beguiling than Dolly the sheep? Note the choice of name and how that cosy image was reinforced by pictures of a little girl's sweater in Dolly's wool being hung in the Science Museum at a time when challenges were increasingly being raised over the engineering of crops.
Though cloned, not engineered, Dolly has become the public face of animal engineering. But behind Dolly's cosy image is a very different story. For example, pigs have been engineered with a human growth hormone to produce "super-pigs". The few who lived were impotent, partially blind, arthritic and unable to stand.
Reports from the independent research centre, the Roslin Institute, make no secret of the problems of "large offspring syndrome" in which cloned animals can be up to five times the normal size. But what have we heard of the suffering of mother animals who carry these monsters, or of Dolly's 12 siblings who died?
Much is said about engineered food helping to feed the world. Yet engineered fish, boosted with human genes, are so impaired in terms of mating and life-span that scientists calculate that even one escapee rejoining its original kind could wipe out the species in 40 generations. At least 11 fish species have been engineered - putting at risk this major food source.
Farm animals are being given human genes not only to boost their value for the table but to "humanise" them, for providing organs for transplants, or to express medical products in their milk, blood or semen. Some of these products may be life-savers. But what kind of society violates the very essence of cattle to make cows' milk marginally better for babies - yet fails to support human breast feeding? Or moves genes between humans and animals, without considering how this adapts animal diseases to humans?
At every turn animal engineering challenges our compassion, our values, and our relationship with the natural world. There are no easy answers or simple choices but I believe it is vitally important to ask the questions.
Moyra Bremner is the author of 'GE:genetic engineering and you'. Harper Collins, pound;6.99