The reversal of aging has been one of the great dreams of humanity. The Harvard Medical School has demonstrated "a dramatic reversal" in the aging process when reintroducing the enzyme telomerase into old and feeble mice. What happened was that their naturally worn out organs started to regenerate, instead of degenerating further, bringing them back to a youthful state of health. Sadly, while the results of this study are hugely important, there are a couple of caveats to make: firstly, the mice in question were genetically modified to suffer from a lack of telomerase, which might have inflated the results of the tests relative to regular mice, but more importantly, an increase in telomerase in humans is a hallmark of most human cancers. So time is required for the technology to mature.