An individual's DNA plays a role in the aging process. Aging begins even before birth, as soon as cells start to die and need to be replaced. On the ends of each chromosome are repetitive sequences of DNA, telomeres, that protect the chromosome from joining with other chromosomes, and have several key roles.
The process of aging starts early in life, even before birth, when cells begin to deteriorate and need to be replaced.  Telomeres, protective DNA sequences found at the ends of chromosomes, are essential for preventing chromosome fusion and have a significant impact on aging.