https://i.stack.imgur.com/KJ9wf.jpg

As you know all DNA carries a bunch of messages.

What you may not know is that it's not just a matter of code in an order.

Instead DNA has multiple levels of structure. See that picture I link to?

DNA is a long line of code. Then that DNA is curled up on itself and wrapped around histone proteins that create super structures.

Not only is the code of DNA part of what says build a hand. But signaling their system proteins and other molecules tells which part of the DNA to read at which times.

Then once RNA is made some RNA is used to make proteins. But RNA can be folded upon itself and make signaling Pathways as well.

So the message of RNA might be use to turn amino acids into proteins. But it also might use to tell cells to turn things on at all.

Other simple molecules like glucose are also used for cell signaling. So the presence or absence of glucose might say to turn a process on or off.

So DNA holds a message. But it's not just read in a strip down the line. Rather the exact same DNA sequence could pump out different final products depending on histone and other involvement. It's very Dynamic we don't totally understand it.

You will hear some people even say that a majority of our DNA is not used. That is that we have not identified why a ton of information in the DNA is there. It doesn't seem to make anything and it might be left over from the past or it might be used to Signal these dynamic processes I'm talking about.