OK, so we have our own DNA library.
(if you want to refresh the concept of DNA is please have a look at my post: https://desciencethescience.wordpress.com/2015/10/26/what-on-earth-is-that-dna/).
If we can endlessly get our instructions and keep on copying them to get made whatever our body needs, why can’t we live forever?
Unfortunately like any other book, material wears out. And surprisingly enough just like with the good, old print: the edges are getting a bit softer, we are losing pages at the beginning and at the end of the book. You might read some letters wrong as they are not as clear cut. Going back to our DNA-RNA-protein analogy: when you make your notes (RNA) from the book (DNA) your cake (protein) might not be as nice as the first time round. Multiply it by all processes in the system, and sooner or later there will be a baking disaster in our kitchen. Guess not so bad if it hits the fruit loaf for Christmas, more problematic if we cannot make our everyday bread.
It is actually not 100% clear why we get old and as our system is so complex, we cannot blame it all on DNA. However we have it proven that errors accumulate with time. Weirdly enough there seems to be a connection between high glucose levels and DNA damage. So maybe let’s keep the doughnuts in our kitchen to minimum 🙂