central dogma of molecular biology: a standalone construct

Francis Crick first stated the central dogma in his 1958 lecture On protein synthesis, and he sharpened and defended it in his 1970 Nature paper Central dogma of molecular biology. It is a rule about how sequence information, the precise ordering of the chemical letters in DNA, RNA, and protein, is allowed to move inside a living cell: information passes from nucleic acid to nucleic acid and from nucleic acid to protein, the familiar route from DNA to RNA to protein, but once that information has reached a protein it cannot be copied back out again, neither from protein into nucleic acid nor from one protein into another. Crick's claim was specifically about the transfer of detailed sequence, not about which molecules generally control which, and he framed it to say what the machinery of the cell forbids rather than only what it permits. What makes it a landmark is its scope: a single directional constraint that organises how genes are read and expressed across essentially all known life, and against which apparent exceptions such as the reverse transcription of RNA back into DNA are measured and found to leave the protein-to-nucleic-acid step still unobserved.[1][2]

Unit

A directional constraint on sequence-information transfer among DNA, RNA, and protein

Recovery means

Not applicable

Measured by

Assessed by tracing whether ordered sequence information can be transferred along a given molecular route, established experimentally through the biochemistry of replication, transcription, translation, and reverse transcription