DOES EPIGENETICS CONTROL AGING?
Interestingly, it has been shown that epigenetic modifications are associated with aging. Gene expression and chromatin modifications (e.g., histone methylation or acetylation, DNA methylation) change with age in many species. Intriguingly, some epigenetic modifications have been proposed to act as “aging clocks.” As noted in an earlier article, certain DNA methylation patterns correlate very closely with a person’s age, suggesting that chemical modifications occur through life. Whether these directly cause aging or age-related features or are simply bystanders of an inherent aging process (like gray hair) is not known. Nonetheless, given that nutrition, exercise, and other environmental effects have been shown to affect DNA methylation, such DNA modifications might accumulate during a person’s lifetime and directly influence gene expression, thereby providing a molecular explanation for the aging process. Identifying and studying individuals who are chronologically old, but have the DNA, physical, and intellectual characteristics of a younger person will be very significant for unraveling the mechanism for retarding aging.