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Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case.

I remember that the case of reverse transcriptase was felt to be different from the existence of RNA viruses because it involved the flow of information from RNA to genomic DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma. The following is a typical illustration of that, taken from some University lecture notes that I found on-line and which are described as:

These diagrams ..., created originally by Crick, summarize the basic processes of information transfer within cells.

But the NCBI collection of facimilies of Crick’s documents include a 1956 diagram that is quite different and much more sophisticated:

And, so the central dogma has not been violated (certainly not by lncRNAs), unless you consider that it has by prions, where information of sorts is transfered from protein to protein.

Morals

1. It’s amazing what you can find on the internet.

2. Never believe what you find on the internet.

Footnote

I’ve seen the DNA → Protein arrow repeated as if it were fact in diagrams, although Crick only said ‘may’. I know of no example of this.

Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case.

I remember that the case of reverse transcriptase was felt to be different from the existence of RNA viruses because it involved the flow of information from RNA to genomic DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma. The following is a typical illustration of that, taken from some University lecture notes that I found on-line and which are described as:

These diagrams ..., created originally by Crick, summarize the basic processes of information transfer within cells.

But the NCBI collection of facimilies of Crick’s documents include a 1956 diagram that is quite different and much more sophisticated:

And, so the central dogma has not been violated (certainly not by lncRNAs), unless you consider that it has by prions, where information of sorts is transfered from protein to protein.

Morals

1. It’s amazing what you can find on the internet.

2. Never believe what you find on the internet.

Footnote

I’ve seen the DNA → Protein arrow repeated as if it were fact in diagrams, although Crick only said ‘may’. I know of no example of this.

Cross Reference

I have just (June 2024) posted an answer to a different question about the Central Dogma on SE History of Science and Mathematics. It attempts to provide a historical context, but may be of more general interest.

Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case.

I remember that the case of reverse transcriptase was felt to be different from the existence of RNA viruses because it involved the flow of information fro RNA to genomic DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma. The following is a typical illustration of that, taken from some University lecture notes that I found on-line and which are described as:

These diagrams ..., created originally by Crick, summarize the basic processes of information transfer within cells.

But the NCBI collection of facimilies of Crick’s documents include a 1956 diagram that is quite different and much more sophisticated:

And, so the central dogma has not been violated (certainly not by lncRNAs), unless you consider that it has by prions, where information of sorts is transfered from protein to protein.

Morals

1. It’s amazing what you can find on the internet.

2. Never believe what you read on the internet.

Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case.

I remember that the case of reverse transcriptase was felt to be different from the existence of RNA viruses because it involved the flow of information from RNA to genomic DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma. The following is a typical illustration of that, taken from some University lecture notes that I found on-line and which are described as:

These diagrams ..., created originally by Crick, summarize the basic processes of information transfer within cells.

But the NCBI collection of facimilies of Crick’s documents include a 1956 diagram that is quite different and much more sophisticated:

And, so the central dogma has not been violated (certainly not by lncRNAs), unless you consider that it has by prions, where information of sorts is transfered from protein to protein.

Morals

1. It’s amazing what you can find on the internet.

2. Never believe what you find on the internet.

Footnote

I’ve seen the DNA → Protein arrow repeated as if it were fact in diagrams, although Crick only said ‘may’. I know of no example of this.

Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case. (It was felt to be different from the existence of RNA viruses because it involved RNA to DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma.)

And, so the central dogma has never been violated (certainly not by lncRNAs), unless you consider prions, where information of sorts is transfered from protein to protein. Hmm, never thought of it like that before.

Crick’s Central Dogma was actually:

The Central Dogma
This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of basesin the nucleic acid or of amino acid residues in the protein.

So, although in my comment I stated that the discovery of reverse transcriptase was the first violation of this — as was generally regarded — this turns out not to be the case.

I remember that the case of reverse transcriptase was felt to be different from the existence of RNA viruses because it involved the flow of information fro RNA to genomic DNA, which were generally represented by a unidirectional arrow in the opposite direction in diagrams of the dogma. The following is a typical illustration of that, taken from some University lecture notes that I found on-line and which are described as:

These diagrams ..., created originally by Crick, summarize the basic processes of information transfer within cells.

But the NCBI collection of facimilies of Crick’s documents include a 1956 diagram that is quite different and much more sophisticated:

And, so the central dogma has not been violated (certainly not by lncRNAs), unless you consider that it has by prions, where information of sorts is transfered from protein to protein.

Morals

1. It’s amazing what you can find on the internet.

2. Never believe what you read on the internet.