We should watch that we don't get too far off topic here so I hope we can clear up the definition of a theory quickly.
I will use a different are of science to illustrate the point.
We know that "gravity" (whatever it is) is a fact. That is there is some attraction between massive objects.
Newton's devised a theory of gravity some centuries ago. It wasn't as interesting as modern theories go because it was the early days of science. He really only codified his observations and made some implicit (but unrecognized to him) assumptions about the nature of space and time. His theory gives us the inverse square law and works with a very high degree of precision.
His theory of gravitation gives us an early
explanation for gravity. Thus the
fact of gravity is explaned by the theory.
However, it turned out there were some descrepancies between Newton's theory of gravitation and actual observations. In other words it appeared that it might be "wrong" in someways. It turns out while being a very good description in a limited range of circumstances it needed to be tweaked and given a hugely different underlying picture of the universe.
Enter Einstein and his theory of general theory of relativity. That is the name but it is his new theory of gravity. It works better than Newton's over a wide range of conditions. It also makes explict some statments about the nature of space/time. The picture of spacetime is enormously different from Newton's implicit picture.
This is the best theory of gravity we have todate. There are reasons to think it is not perfect either. It is clearly correct over a very, very wide range of circumstance but it doesn't handle everything.
The fact of evolution is observed in both what living things do today (we see macro-evolution at the species and even higher levels today) and it is observed in the record of life on the planet over the last 3 to 4 billion years. This is the fact that needs to be explained.
The theory of evolution is the explanation for both how life produced the pattern we see over 3 billion years and what we see happening today.
Any comment on the DNA code you talk about would be off topic here.
However, it also has nothing to do with evolutionary explanations in any case. Evolution (as we are using the term here) refers to biological evolution -- that is, the evolution of living things. Anything to do with how the first living thing arose is not biological evolution it is chemistry.