The bloggers at Evolution News & Views (sic) are promoting another creationist book [see Biological Information]. This time it's a collection of papers from a gathering of creationists held in 2011. The title of the book, Biological Information: New Perspectives suggests that these creationists have learned something new about biochemistry and molecular biology.
One of the papers is by Jonathan Wells: Not Junk After All: Non-Protein-Coding DNA Carries Extensive Biological Information. Here's part of the opening paragraphs.
James Watson and Francis Crick’s 1953 discovery that DNA consists of two complementary strands suggested a possible copying mechanism for Mendel’s genes [1,2]. In 1958, Crick argued that “the main function of the genetic material” is to control the synthesis of proteins. According to the “ Sequence Hypothesis,” Crick wrote that the specificity of a segment of DNA “is expressed solely by the sequence of bases,” and “this sequence is a (simple) code for the amino acid sequence of a particular protein.” Crick further proposed that DNA controls protein synthesis through the intermediary of RNA, arguing that “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.” Under some circumstances RNA might transfer sequence information to DNA, but the order of causation is normally “DNA makes RNA makes protein.” Crick called this the “ Central Dogma” of molecular biology [3], and it is sometimes stated more generally as “DNA makes RNA makes protein makes us.”
The Sequence Hypothesis and the Central Dogma imply that only protein-coding DNA matters to the organism. Yet by 1970 biologists already knew that much of our DNA does not code for proteins. In fact, less than 2% of human DNA is protein-coding. Although some people suggested that non-protein-coding DNA might help to regulate gene expression, the dominant view was that non-protein-coding regions had no function. In 1972, biologist Susumu Ohno published an article wondering why there is “so much ‘ junk’ DNA in our genome” [4].
- Crick published a Nature paper on The Central Dogma of Molecular Biology in 1970. Did he and most other molecular biologists actually believe that "only protein-coding DNA matters to the organism?"
- Did Crick really say that "DNA makes RNA makes protein" is the Central Dogma or did he say that this was the Sequence Hypothesis? Read the paper to get the answer—the link is below).
- Is it true that, in 1970, the majority of molecular biologists did not believe in repressor and activator binding sites (regulatory DNA)?
- Is it true that in 1970 molecular biologists knew nothing about the functional importance of non-transcribed DNA sequences such as centromeres and origins of DNA replication?
- It is true that most molecular biologists in 1970 had never heard of genes for ribosomal RNAs and tRNAs (non-protein-coding genes)?
- If the answer to any of those questions contradicts what Jonathan Wells is saying then why do you suppose he said it?
Crick, F. (1970) Central Dogma of Molecular Biology. Nature 227:561-563. [PDF]
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