To say it simple, for ages science has said that most of the genetic material in our bodies exists to simply be available when the main operating genes need it. The thing we are finding out is that this more-or-less passive material is really the "switching" material. It is the controllers of the main genetic material, switching genes on and off in highly complex patterns, that allow us to live and flourish. This switching material has safeguards built in to correct itself against bad mutations that comes about from environmental "poisoning." But, the corrections gradually deteriorate, and that is why we age.