What are some reasons as to how large differences in DNA can exist without influence on the resulting protein?

Question

related to analysis of gel electrophoresis

Answer 1

That statement is not entirely true, or rather vague. There can't be "large differences" in the DNA and end up with the same protein.

However, there is some room for differences in the DNA. Take a look at the codon for amino acids:

http://algoart.com/aatable.htm

There you can see all the different codons for amino acids. The most popular variable base is the "wobble position" or the last of the three. If you look at the table again you'll notice that for each amino acid the first two bases of the codon are usually the same but the last base can vary. Essentially, you could have two pieces of DNA differ by 33% and still produce the exact same protein.

In a more broad sense, the action of proteins usually occurs at a small site while the rest of the protein is just support structure. Similar amino acids can be swapped in these support areas with little to no effect on the activity of the protein.