This is because identical twins are conceived at the same time and in the same environment, are nurtured in the same womb, and born into an identical milieu. These are, of course, identical twins – and these naturally produced clones are closer to their twin sibling than any that might be made artificially. Mere mention of this seven-letter word seems to send many of my journalist friends into a complete spasm. It can’t be because of alarm at the prospect of making identical people – there are at least 25,000 human clones in Britain already.

Enthusiasts for cloning are asking for trouble if they make exaggerated claims on behalf of a technology that is undeveloped and fraught with dangersIt is difficult to understand the massive media interest in cloning. All of this explains my excitement, which I am pleased to share.Dr Robin Lovell-Badge is head of the division of developmental genetics at the MRC National Institute for Medical ResearchThe case for cautionCut the hype, says Britain’s favourite medical scientist, Robert Winston. It may help us find the genetic cause of rare diseases where there are simply too few patients to work with. And it can allow drug companies to better test potential pharmaceuticals for their effects on different people – why some respond well and others adversely or not at all – and to do this before marketing the drug.

“Therapeutic cloning” is essentially taking a biopsy from a patient and turning it into useful cells that can then be used for therapy without fear of graft rejection, which is the most common reason why transplants fail.Of course, this type of treatment is a long way off widespread use, and it is not going to be cheap We also need to know how reliable the method will be. Moreover, if it is to be used clinically, it will have to be as personalised medicine: we are not talking about pills from the pharmacist. But this could be a once-only treatment that will improve the quality of life for an individual and extend life in a productive way.The current cost of treating someone with diabetes and the complications that can arise from this are huge, as are those for cardiovascular problems, or any degenerative disease that requires long-term care Using cloned cells may make it all unnecessary. They can be used to study aspects of genetic disease in the culture dish.