The original post: /r/askscience by /u/A7med_gomaa on 2024-11-10 08:03:44.

What is the precise reason that cells lose their ability to regenerate over time? And which genes primarily control the process of cellular regeneration? Are these genes present in each cell individually? If so, why do cells in the body not vary in their regenerative capacity with age according to the nature of each cell and the conditions it is exposed to? In fact, we observe that cells age at nearly the same rate, with little variation between them in this regard. Or is it that the genes driving aging in different cells of the body act synchronously and share the same nature, which is why we see a simultaneous aging process across cells? Alternatively, is cellular regeneration directed by a central mechanism that guides all body cells toward this process? If so, where is this central system located? Is it in the brain, or is it in another organ?