Thousands of infertile men might benefit from a world first in which scientists artificially created sperm in a test tube. Researchers made sperm in the laboratory from mice stem cells and this was then used to ‘father’ seven mice, six of which lived into adulthood. The scientist in charge of the project said it was possible some forms of male infertility could be treatable within five years. In some infertile men, all the right apparatus exists to make sperm but they do not do so, suggesting an ‘environmental’ rather than genetic problem. It is believed the artificial creation of sperm could enable scientists to use samples of testicular tissue from infertile men to grow functional sperm in the laboratory and then put them back into patients so they could impregnate their partners. A similar technique could be used to restore fertility to men, and particularly boys, who have undergone radiation treatment for cancer by taking a sample before the procedure and transplanting it back afterwards. However, some experts were cautious about the potential, pointing out that the mice were born with abnormalities similar to the kind seen in cloned animals such as problems with growth, […]