Why do epigenetic changes accumulate with age?
Epigenetics are the "markers" that determine which portion of our DNA is meant to be used at a given time, by a given cell. Since each cell contains a complete copy of the entire organism's DNA, not all of that DNA can be used simultaneously, particularly if a cell is attempting to be specialized in a particular role in a multicellular eukaryote, such as a skin or bone cell.
The only DNA that cell should be using is the DNA relevant to its specialization; the skin cell would "deactivate" the bone genes, eye genes, and so forth. Since actually cutting out...
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