How long can human beings live? Is there an outside limit? Do we know enough about aging to break through possible biological barriers? Is the current approach to curing "age associated diseases" like Alzheimer's flawed? Experts are sharply divided. In 1962 eminent biologist Leonard Hayflick discovered that normal human fetal cells replicate a limited number of times. This phenomenon promptly acquired the moniker the "Hayflick Limit." Later, biologists Calvin Harley and Carol Greider provided the molecular explanation for the Hayflick limit with their discovery that telomeres, the DNA biological material in every cell of our bodies, diminish each time cells divide. In contrast, cancer cells,
Forget those expensive anti-aging creams. Soon we might be able turn back the biological clock for real. Some scientists are now saying that there may be ways to stop the inevitable aging process by using certain genes to reset cells. They’ve already done it with mice. Researchers at the Salk Institute in La Jolla, Ca., have published a study in the medical journal, Cell, that details how they use genetic modification to rejuvenate the organs of laboratory mice and increase their lifespan significantly. One word of caution: The process still hasn’t been transferred to actual humans. “Obviously, mice are not humans and we know it will be much more complex to rejuvenate a person,” said Professor