Hi
I'm an ordinary guy that decided to learn biology last week. I've been reading for a few days on my own and I'm really puzzled about what the scientists call "Junk DNA" which accounts for 98% of our DNA and the rest codes proteins(please tell me if I got it wrong).
To me it’s absurd that they would call it junk, maybe I'm going out on a limb saying this, but I’m almost certain that this "Junk" is what makes everyone of us unique. So the thought that struck me is that our Junk DNA has a purpose and it’s to give instructions to our known DNA on for an example, size, shape and appearance. When we talk about size, the junk DNA doesn’t have to control it directly, but it could for an example also code for the amount of HGH a body produces and when the growth plates will fuse, thus indirectly it would still determine the final products appearance.
And then we have identical twins who share the same DNA. But! , they only share the same known DNA, not junk DNA. I've not read about this but I’m pretty sure this is true, since we are nowhere close to mapping our junk DNA. You can still notice differences in facial structure, height etc in identical twins and I believe that’s because their Junk DNA is not the same. Though some parts of it may be identical, and some parts may be similar.
And then we have a bacteria with only 2-3% Junk DNA. Only a fraction compared to humans and other large organisms. That number is not random, that’s why I would think, the bacteria is so small and simple, it doesn’t have a lot of instructions for its appearance.
Curious what you educated people would have to say about this.