The codon table is ordered in a really specific way. The sequence UCAG progresses along the first base, then the second, then the third. Does it occur exactly that way in nature, is it inspired by the way it occurs in nature, or is it totally arbitrary? I can’t find any information on this.
Thank you
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I believe you are misunderstanding how a codon table works. A codon is a sequence of three base pairs (A, C, G, and T/U), or letters. No codon is ever four base pairs, always three. This is universal across all organisms and viruses, a codon is always three base pairs. The codon is read by the ribosome as corresponding to one of 20 different amino acids. So, let’s use [this](https://images.app.goo.gl/MqyTtfQdZQxnH1qz8) codon chart and read the codon UUC. The first base in the codon is U, so we start at the big U in the middle. The second letter is also a U, so we move from the U to the medium sized U, then to the last base of little C. This gives us the amino acid Phe (short for phenylalanine). Visually, you read UUC [like this](https://i.imgur.com/PDOB54T.jpeg)
Now, there are two things I want to point out. First, had the codon been UUA, that would give us Leu (leucine). This shows how each codon sequence is distinct and helps your body construct proteins in the proper way, as coded for by your DNA.
Second, see how the codon UUU would have also given us phenylalanine? This is called wobble, and helps keep some mutations silent, or having no effect, as a mutation of C (cytosine) into U (Uracil) means the same amino acid is still coded for.
Edited for clarity
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