“Basically, these worms lived to the human equivalent of 400 to 500 years,” he says. Each of these alterations extended the worm's lives ___________. What is remarkable is that when they are added together, the combined impact turned out to be much greater.The research may explain why it has been difficult to identify single genes that are responsible for the long lives enjoyed by centenarians.“It’s quite probable that interactions between genes are critical in those fortunate enough to live very long, healthy lives,” says Dr. Kapahi.