As I said, mapping out the analogy and disanalogy can teach you quite a bit. You’ll find the analogy is quite good in some domains, and so it’s the basis a lot of scientific work. But outside those domains the analogy falls apart quickly, and some times spectacularly. So it isn’t the only way that scientists study DNA, not by a long shot.
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I feel the need to further clarify for @LyghtWayve. Note that the term “genetic code” has a specific meaning: it refers to the mapping between three-base codons in your DNA (and the mRNA transcribed from it) and particular amino acids in the proteins translated from the mRNA. Thus if the genetic code is considered to be a code, only around 2% of your genome is involved in that code. The genetic code is rather like a real code in some respects, as the mapping between codons and amino acids is arbitrary, as is the mapping between symbols in a code and pieces of unencrypted text. (Let’s ignore the difference between a code and a cipher; Morse code, for example, is a cipher.)
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Yes. And to add to that, in the particular context of creationist thinking:
The reason one winds up with a lot of arguments about whether DNA sequences are a “code,” or flagella are “motors,” in the creationism context is that people tend to make the mistake of thinking that terms such as “code” or “motor” have in themselves the power, once applied to a thing, to dictate other conclusions about that thing. It’s just a variant on the old “a creation needs a Creator” argument. If DNA is a code, or a flagellum is a motor, so the argument goes, well, we know that “codes” usually are the sorts of things nerds write and “motors” are usually the sorts of things mechanics build, so all life must be the product of a nerdy mechanic.
As a retired lawyer I have some sympathy for why that’s such an appealing line of thought for some people. In the law, that can actually work. For example, we argue about whether a particular arrangement is a “contract” or not because if you can get the ball over that line, the classification of a relationship as a “contract” entails a whole bunch of other concepts which, by virtue of that magic word, now automatically apply to the relationship. If you’re just short of a “contract” they don’t apply; if you barely have a “contract” they do. But that’s an artifact of the manner in which law, a heavily “verbal” discipline, works. In the real world, one can conclude that by some definition or other a flagellum is a “motor” and this entails – well – nothing at all. No inference or conclusion follows from it; any inference to be drawn has to depend upon the underlying facts, not upon the choice of terms to describe those facts.
So, are DNA sequences a “code”? By some definitions, literally yes. By other definitions, literally no, metaphorically or analogically yes. By still other definitions, “no” all around. And the choice of definitions for the word “code” is the only thing which changes as that answer changes. Reality – the facts about DNA and how it functions – does not change as our descriptors of it change.
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Is that true? Lately I’ve been reading different theories about the origin of tRNA. The direct template theory proposes that before tRNA, amino acids bound directly to RNA templates. But I don’t know if this theory is widely accepted.
Not trying to be snarky - I really want to know.
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You are right @stlyankeefan. In several ways the genetic code is not an arbitrary mapping.
Same is true, by the way, of the ASCII code. In some ways it is not, actually, arbitrary.
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What is your opinion of the template theory? All of the papers I found on it were pretty old, but there are recent papers showing RNA will directly bind to amino acids. Is the theory dead or is it still being considered?
Thank you. This is an excellent point. It reminds me of what Douglas Hofstadter said about how we use analogies in virtually all of our thinking. While they make thinking easier, we must not confuse our language or description of something for that things actual reality. So when we assign code to something, we must understand that DNA does what it does no matter what we call it. Thus we must be careful when we try to bring everything about a code and apply it to DNA.
This leads to several thoughts, in fact. One thought is that if we hew too closely to the code analogy, we may miss something about DNA where it is not like a code but is actually extremely important and significant to it. It also reminds me of what @swamidass said when he stated that DNA predates humanity and human coding approaches so we need to think carefully about that.
Another critical point is that I think this actually extends to all of science. We must be careful and realize that our descriptions of reality might not contain all the facts and attributes of reality. The universe obviously predates us both temporally and ontologically. Our scientific language describes some aspects quite well but it is likely there is more to discover that may actually shock us. This is why I am so excited about future research.
Your comment is very insightful.
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Define “code”?
And welcome to the forum!
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Thanks for the additional insight.
Absolutely. We use analogies all the time to explain biology, but they always break down, sometimes in spectacular ways. A good rule of thumb is that analogies should never be considered as arguments.
And no abstractions are involved.
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It’s being actively worked on. I know Nick Lane’s group at UCL are doing experiments on the stereochemistry hypothesis. I saw a public talk of his recently where he indicated that the phenomenon appears to be real, that there are relatively weak but consistent interactions between amino acids and their RNA codons (or anti-codons).
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Thank you.
I did not have a definition of code myself. I just have heard people talk about it as such and wanted to hear why many scientists do not think it is an actual code.
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As you can see there is a lot to be said about it both ways. Good conversation starter! 
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Thanks!
It still depends on what is meant by code.
This is often a huge sticking point.
First the pedantic stuff. The “genetic code” does not refer to DNA or RNA. The later of which are long polymers of nucleotides. Also whether a section of DNA/RNA codes for protein or not doesn’t change the fact that it is still DNA/RNA. There is such a thing as non-coding DNA after all (most of our genome in fact). The “genetic code” (or rather “codes” since there are slightly different versions) is the correspondence between triplets of nucleotides to the amino acids in proteins. This below is (one common version of) the genetic code:
But then the question becomes: isn’t the “genetic code” still a code? First, what is a code?
A code is a list of words or phrases in place of the actual words or phrases. For example, secret missions often use code names. Translating a coded message requires a code book that lists all the used words/phrases and shows what they mean. On the other hand, you have ciphers that require a simple set of rules that changes each symbol to another simple or set of symbols. This means that Morse code is not actually a code, it’s a cipher. Likewise, the “genetic code” would be more akin to a cipher rather than a code.
Okay then, is the genetic cipher not just akin to a cipher, but an actual cipher? By the definition given above, that would be a no. We might use symbols to refer to the nucleotides (ATCG) and amino acids (ALA, MET, TYR, etc), but these are just abbreviations of the words that we use from our vocabulary. The codebook that we constructed to refer to these things. Nucleotides and amino acids themselves aren’t symbolic, genes and proteins don’t have semantic meaning. That’s the big difference. [Before someone yells genes have information, information is not the same as semantic meaning. Gibberish is still information. Type something randomly in a word doc and save it, it will still take up storage]. One might argue that despite this, there is still a significant similarity, but that would admitting that it is an analogy.
It’s simply the case that we carry the baggage of the words that scientists have used in the past to name phenomenon that they observe. They often described the newly discovered by drawing similariteis what they are already familiar with. The words “translation” and “transcription” are more terms obviously borrowed from computer science, but the literal descriptions of these processes would be “RNA template directed protein synthesis” and “DNA template directed RNA synthesis” respectively. To give a more obvious example, ever wondered why cells are called “cells”? It’s because one scientists (Robert Hooke) observed a piece of cork under a microscope and saw the cavities within them. These reminded him of the architecture of cells of prison.
Now, whenever anyone says to me that the suggestion that the genetic code is not a code is ridiculous as it is obvious from how it is called. I will make the following joke. When I first learned cell biology, I got really confused after finding out that among all the trillions of cells in our body there is not a single inmate to be found.
Hope this helps. Also, welcome to the forum.
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This is completely wrong. DNA is not translated to proteins. When a gene is expressed, DNA is transcribed into messenger RNA (mRNA) and mRNA is then translated into the protein by the ribosome.
More importantly, DNA is not the material used to build what is encoded. Proteins are not made of DNA or RNA. Proteins are made of amino acids.
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I think the analogy breaks down if you say that DNA is “a code” instead of “code”. You’ll notice that you used it both ways in your post.
Saying that something is like “a code” would usually be in comparison to something like Morse Code or ASCII. “Code”, on the other hand, could refer to information incoded into a particular code. For example, a message sent in Morse code is code or coded information.
So, DNA is not a code, but the genetic code is (a code). It is a mapping of the relationship between codon and amino acid.
DNA can be seen as a storage medium, like a computer tape. No one would say that a computer tape is a code. They would say that the tape stores coded information.
The information in the sequence of bases in a gene is coded in the codons of the genetic code, just like the information of a message is coded in the groupings of dots and dashes of Morse code.
Here is a simple animated video that I think will be helpful.
Like you, I’m a computer programmer, and an understanding (at a basic level) of how the processes of transcription and translation work was very helpful for me to understand the arguments concerning DNA, codes and coded information.
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Yes, I skipped a few steps. Mea Culpa.
DNA and the final protein are both made of amino acids, so the information media and the building material is the same in that respect, and I should have been more clear. This sharing is not unheard of in human codes (ex: a book on Origami) but isn’t how most codes are used.
The message in DNA is chemical, and is “decoded” by the laws of chemistry and physics as the function of the protein. This is again unlike human codes, which require the sender and receiver have a common understanding of how the (de)code information (ie: a shared language or a cypher).
In the case of gene expression, the sender is the group of enzymes that transcribe the DNA information into mRNA and the receiver is the ribosome which translates the mRNA into a protein.
I think a reasonable, if imperfect, analogy is to think of a gene expression as sending a file to a 3D printer to produce an object.
In the 3D printer analogy, the printer doesn’t need to understand the function of the object being printed. It just follows the instructions found in the file being processed. The same is true for the ribosome building the chain of amino acids according to the codons of the mRNA being translated.
Shannon and Kolmogorov have little to do with the topic of codes being discussed (they do have a lot to do with transmitting strings of data across a communication channel, though). Why bring them up?