Efforts to help humans live longer will face big challenges: a genetic evolutionary system that has no particular interest in helping people live past their peak productive years, and thousands of genes that can go wrong in different ways in different people.
But there is still reason for optimism, says Dr. George Martin, professor of pathology, adjunct professor of genetics, and associate director of the Alzheimer Disease Research Center at University of Washington School of Medicine, Seattle.
"A study of evolutionary biology offers both good and bad news. The good news is that life span, like all life-history traits, is plastic. We know this because in the laboratory, you can take fruit flies and select for fruit flies that can live 50 percent longer than usual," Martin says. "If nature is given a chance to devise better alleles and mechanisms for protecting macromolecules, that will happen. So there is an opportunity for substantial increments in human life span.
"The bad news is that there are so many different things that can go wrong as we age. These can be affected by an enormous number of potential inborn genetic variations that can modulate how we age; they come in different combinations in different individuals. Difficult, expensive and customized interventions may therefore be required to achieve substantial gains in life span."
Martin discussed the topic of genetics and aging during "How Long Can Humans Live?" as a panelist at the American Association for the Advancement of Science annual meeting on Feb. 18.
Martin established one of the earliest Alzheimer's research centers, where he and his research team recently mapped two of the genes responsible for early-onset Alzheimer's disease. He is the author of more than 250 articles and book chapters, has served on the National Advisory Council of the National Institute on Aging and has been elected to membership in the Institute of Medicine of the National Academy of Scienc
Contact: Walter Neary
University of Washington