Here, you may find this interesting. It's an excerpt from an article on how some time in the future we could become immortal. I found it interesting.
Really, the only thing keeping you from having the lifespan of a vampire or a Highlander is an enzyme called telomerase.
So if you've decided you want to live until squid evolve to start swinging from trees, the first thing you should know is that while we accept aging as an unquestioned constant of the universe, it really isn't. The breakdown in our cells that causes us to get frail and wrinkly is a specific set of defects that science is just now starting to pin down. By all rights we shouldn't have to get old. After all, nature has plenty of examples of animals that suffer the whims of weather and disease, but if left alone in a germ- and disaster-free habitat would effectively live forever (including tortoises, certain jellyfish and some plants).
With us, there is that enzyme, telomerase, which acts like the little plastic thingy on the end of your shoelaces for your DNA -- it keeps the ends of your DNA from unraveling. Unfortunately, every time your cells divide, some of this is lost, meaning you are breaking your body's ability to regenerate itself every time you grow or heal. Medical scientists are finding ways to either rejuvenate telomerase or prevent its loss in the first place. If they succeed, that could effectively halt or even reverse the aging process. At that point, youth could not only be wasted on the young, but also completely blown on the elderly, who would likely forget all their hard-earned wisdom with their reinstated endurance and sudden return of fully functioning boners.
And one way or the other, the answer to aging is in our genes. And gene therapy -- that is, manipulating the genes inside our cells to treat disease -- is already a thing. It's just a matter of getting better at it. Futurists Ray Kurzweil and Dr. Terry Grossman think that eventually we could not only block disease-causing genes, but even introduce new genes that, in addition to preventing aging, also make awesome augmentations like changing your eye color or making you glow in the dark.
None of these techniques will save you from a fiery car crash, obviously, but the point is there is no reason to think of a lifespan as something that has to end in 80 or even 800 years, barring deadly intervention from a jealous husband.
