Research into Aging and Extending Life Span

The mounting evidence for age genes that influence the aging process is by no means conclusive, but it is quite impressive,coming from a variety of independent research from aging in worms and fruit flies to antioxidants and gene repair mechanisms, and human mutations. Still, the connections are circumstantial.

Christopher Wills, professor of biology at the University of California in San Diego, thinks that by 2025 science will likely isolate the mammalian age genes in mice. We share roughly 75 percent of our genes with mice and have much the same body chemistry; this is a strong reason to believe that an age gene found in mice could also be at work in humans. if such genes are located, the next step would be to find out if these age genes have their counterparts in humans.Wills believes that if they are found in humans,they may extend the human life span perhaps to 150 years.

But by 2020, when personalized DNA sequencing becomes widespread. a second tactic may prove fruitful as well. By analyzing populations of healthy individuals in their nineties and beyond, scientists will find it possible to use computers to compare their genetic backgrounds and cross-check for similarities in key genes that are suspected of influencing aging. A combination of studies on the DNA of long-lived animals and on the personalized DNA sequences of elderly individuals may considerably narrow down the search for the age gene.

As yet, none of these methods can prove that we can increase the human life span. Indeed, the only theory with a proven track record of extending the life span of animals is the caloric restriction theory, which states that animals which consume calories just above starvation levels live significantly longer than the average. Although this theory flies in the face of common sense (a well-fed animal is well nourished and healthy, and should have greater resistance to disease and aging),it has held up under repeated testing among a wide range of animals. Scientists have consistently increased the life span of rats and mice in the laboratory by 50 to 100 percent.it is the only laboratory-tested theory of age extension for animals that has held up under decades of careful scrutiny, Why?

Across the animal kingdom, the life span of animals is roughly inversely correlated to the metabolism rate. The slower their normal metabolism rate, the longer their normal life span. In 1996,in a study that reduced the calore intake of 200 monkeys by 30 percent,the monkeys were shown to have a slower metabolism rate,a longer life span,and reduced rates of cancer, heart disease, and diabetes. “We have known for 70 years that if you feed laboratory mice less food, they age slower, they live longer, and they get diseases less freauently. We find that monkevs respond in the same wav as rodents and that the same biological changes may be in play here,” says George Roth of the National Institute of Aging.

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