The secret to immortality lies in a lab, and began with research on fruit flies. Playing around with fruit flies genes, scientists found that they can double the fly's lifespan! Using mice, scientists can create extra violent mice just by changing some genes (the ones that control the enzymes). Fukuyama summarizes some recent work on if genes determine intelligence etc., and noted that now scientists "have also been able to produce mice with superior memories through genetic modification- (Fukuyama, Our Posthuman Future, 2003, pg. 24). Making a super-mouse is just the front line of the generically engineered creations - right in front of super-humans. But they don't stop there. Regeneration is also under this category of engineering for immortality, and other scientists have discovered that mice can even regenerate parts of their bodies! .
Advances in stem cell research allow scientists to regenerate virtually any tissue in the body, such that life expectancies are pushed well above 100 years. "Stem cells have the potential to become any cell or tissue in the body and hence hold the promise of generating entirely new body parts to replace ones worn out through the aging process- (Fukuyama, Our Posthuman Future, 2003, pg 60). With the help of research from Progeria, which is a disease that accelerates the aging process in children, researchers discovered what aging is controlled by! It seems the controlling factor is a piece of DNA called telomere (T). This telomere stops DNA from fraying, but gets shorter with each division, and eventually gets too short to protect DNA fray. This is when the cell dies (Hayflick, Mortality and Immortality', 1997). So if scientists can reverses this process (the opposite of what happens with Progeria), they could reverse the process. And that is exactly what they do by genetically engineering the enzyme telomeres. .
There is another possibility of aging brought up by Leonard Hayflick.