What exactly is cloning and do I need to worry about it?

Cloning is "making a copy of a plant or animal by taking a cell from it and developing it artificially'. There is nothing new about this — plants were cloned in Ancient Greece over 2,000 years ago, and the first cloned frog appeared in 1968. But interest in cloning grew in 1997 when Dr Ian Wilmut and his colleagues from Edinburgh University announced the birth of the world's first cloned sheep, Dolly (some people pointed out that since all sheep look identical anyway, how could anyone tell?). However, many people were worried: what if the same techniques were used for some rich, elderly person to reinvent himself; or if an evil dictator produced hundreds of copies of himself in order to take over the world; or grieving relatives used cloning to bring their loved ones back to life?

The truth is that there is no chance that any copy of a human being would be identical either physically or mentally, any more than children are identical to their parents. The possible benefits of cloning, however, are numerous, for artificially producing human tissues and organs for transplant, and for preserving endangered animal species to name but two. Biologists have already genetically engineered headless frogs so it may in future be possible to clone headless humans whose organs could be used for transplants. But would we want to?

How can transplants from other animals help humans?

In one famous case, a British girl born with a rare bone condition that left her with only one ear, had a new one grown for her at the Massachusetts Eye and Ear Infirmary in the USA. By taking cells from her existing ear and transplanting them onto the back of a mouse, scientists grew her another one, which could then be transplanted back. American scientists have also used sheep blood cells to make a universal blood which could be given to any patient, regardless of their blood group while British scientists are close to manufacturing artificial blood, with the aid of milk from genetically-altered cows and sheep. Scientists have also transplanted monkeys' heads on to new bodies, paving the way for head transplants to be performed on humans. The monkeys were able to eat, drink and sleep normally Robert White, head of neurosurgery at Case Western Reserve University in Ohio said the operation could be available to humans within thirty years, but the experiment has been condemned as an example of 'the disastrous route Western medicine is taking, in which prolonging individual life takes precedence over everything'