Scientists Uncover Secret of Long Life

A study conducted at the California Institute of Technology in Pasadena, California, found a common genetic mutation in people over 100 years old, a finding, researchers say could be a key to discovering a way to avoid the ravages of aging.

Scientists found that centenarians were five times more likely than others to have the same mutation in their mitochondrial DNA, the portion of DNA located in the mitochondria or "powerhouses" of the cell that passes only from the mother to offspring. The mitochondria captures the energy released from the oxidation of metabolites and convert it into energy.

Researchers say it is possible that in the process of replication, these molecules are less damaged by oxidation. In the group of 52 Italian centenarians, they found a common mutation in the same main control region. Looking at mitochondrial DNA in white blood cells, they found that 17 percent of the 52 had a specific mutation called C150T transition, compared with only 3.4 percent of 117 people under the age of 99. To see whether the mutation is inherited, researchers studied skin cells collected from the same individuals between nine and 19 years apart. In some, both samples showed that the mutation already existed, while in others, it either appeared or became more abundant during the intervening years. These results suggest that some people inherit the mutation from their mother, while others acquire it during their lifetime, researchers said.