The DNA markers from the blood of healthy centenarians are more similar to those of people in their 20s than people in their 70s. These differences could someday be used to determine biological age — whether a person’s body functions as older or younger than their chronological age.

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The DNA markers from the blood of healthy centenarians are more similar to those of people in their 20s than people in their 70s. These differences could someday be used to determine biological age — whether a person’s body functions as older or younger than their chronological age.