Animal studies show you can simply make a mix of the tissue and inject it all back under pressure,'' says Dr Fishel, head of the Centre for Assisted Reproduction in Nottingham."From there, the precursors start to migrate to the place where they would normally be. Then, when the hormones come along at puberty, they are triggered to start producing sperm. We know from the research that has been done that we can do it in animals. We already know we can take the same kind of tissue and put it in a mouse or a rat testes which will then produce human sperm."No one has done it yet with humans, but if we were given the funding we would have it cracked within three years. Without funding, the research will be piecemeal and it could take 10 years.''He says that one of the problems with preserving both sperm and testicular tissue is that the young patients and their families are not always aware of the option."When you have a terribly sick child, everyone is focused on saving the life of that child, and there is only a very small window of opportunity to take these samples. At this time, issues about future fertility often get a very low priority."But then, when the child survives and reaches adulthood, fertility suddenly becomes the most important thing for the young man, when he realises that he is sterile and cannot have children.''Dr Mohamed Taranissi, medical director of the Assisted Reproduction and Gynaecology centre in Harley Street, agrees.

"It is a growing area because of advances in cancer treatment, but one of the problems is that a lot of people don't know the option is open to them When cancer occurs, everything focuses on that. If it does not get mentioned at the time, they lose the opportunity. People need to be aware of what is available,'' he says.New treatments are also generating a thirst among researchers for further advances. Some believe, for example, that it is feasible now to use the human sperm generated in the testes of rats and mice to actually fertilise a woman's egg.Parents of children with cancer, too, are increasingly searching for new treatments, some of which raise extraordinary ethical problems."I have had a request from a father of a 10-year old boy about to undergo chemotherapy, to take part of the father's testes and preserve it so that it could be put into the boy if he was sterile after the treatment,'' says Dr Fishel.That would result in the boy ejaculating his father's sperm. In effect he would be ejaculating sperm that would conceive his own half-brother or -sister.

That is a mind-boggling ethical concept.''Mind-boggling it may be, but it is already theoretically possible.. We have the paralysis of the big record labels to thank for the fact that the prodigy-circus has ground to a halt. Perhaps, too, the transience of prodigies' marketability has also sunk in, for very few go on - like Maxim Vengerov - to become prodigious adults. On the other hand, the ex-prodigy circus spins ever more desperately.

Having invested fortunes in temporary tots, the record labels must recoup. Vanessa-Mae may have disappeared in a puff of pink smoke, but Nige has been harnessed to Rover cars, and Leila Josefowicz has become the face of Chanel's Allure perfume. There's still gold to be mined from those hopeful seams, particularly if fiddles are involved. We have the paralysis of the big record labels to thank for the fact that the prodigy-circus has ground to a halt. Perhaps, too, the transience of prodigies' marketability has also sunk in, for very few go on - like Maxim Vengerov - to become prodigious adults. On the other hand, the ex-prodigy circus spins ever more desperately.