In his laboratory at the University of Colorado, molecular biologist Thomas Johnson is studying a translucent worm no bigger than a printed comma. In this simple animal, composed of just 959 cells, Johnson believes he may find the answers to complex questions that have eluded scientists for centuries:
What makes us grow old? Can we stop aging, or at least slow it down?
By breeding tens of thousands of these nematodes, Johnson has created a strain that can live for about five weeks--about 70% longer than the worm's average three-week life span. It appears that the difference between the elderly worms and their shorter-lived counterparts lies in a single gene. Now, Johnson is trying to isolate that gene, and he says he is close.
And if genes can be manipulated to extend the lives of worms, the 48-year-old researcher asks, might not the same be true of people?
"Maybe there are major genes in humans that, if we alter (them), we could project a longer human life span," Johnson said. "This would be an absolutely tremendous sociological finding. It would affect . . . every aspect of the way we live our lives if we all of a sudden had average life spans of 120 years instead of 70 years."
Tremendous indeed. Johnson's work is on the cutting edge of a fascinating scientific sojourn, a modern-day quest for the legendary Fountain of Youth. He is among a growing corps of 2,000 molecular biologists, geneticists, immunologists and other researchers across the United States who are trying to unlock the secrets of aging.
They are tinkering with genes, human growth hormones and new drugs, and with strategies of diet, nutrition and exercise. They are studying patterns of survival in worms, fruit flies, mice and people. They are examining the links between aging and illness--cancer, Alzheimer's, Parkinson's, osteoporosis, heart disease, stroke--as well as the effect of environment on aging.
Their strides in recent years have been so significant that a startling new body of thought has emerged, one that says humans may one day live much longer than anyone dreamed possible. Some go so far as to say that the maximum life span, now at 120 years, and average life expectancy, about 75 years in the United States, could double or triple.
"The ideal of all of our work is that sometime in the future, we would take pills that would slow or postpone our aging," said UC Irvine biologist Michael Rose, who is breeding fruit flies that can live up to three times as long as the average fly. "That's the ultimate goal, the man on the moon for all this research. We're not going to have that in five years. But someday it will happen."
