I'm sorry, Larry, but as a response to creationist distortions with respect to "junk DNA," this YouTube video is pretty weak stuff. The evidence it cites are some of the early papers regarding tRNA sequences. While it's true that tRNA sequences (and rRNA sequences) are never translated into protein, these are certainly not what the creationists refer to when they attack the concept of junk DNA. We routinely refer to these as "genes," and the label is appropriate. What the video blogger has focused on is the (mistaken) notion that the only functional DNA sequences are those that code for proteins. That's really just a poor choice of words by the creationists, who could easily respond by a "clarification" that they actually meant was DNA that is not transcribed into one of the forms of RNA used to synthesize proteins. At a stroke, that covers mRNA, tRNA, and rRNA. A much better rebuttal would focus on the longstanding understanding that much of DNA (relating to the c-Value Paradox) could be understood as regulatory and control elements (Think the Britten-Davidson model). That model made it clear that many of the highly repetitive sequences in DNA could be explained in terms of gene regulation. Regulatory sequences are clearly not "junk," and that's been understood at least since the 1960s. (Ken Miller)
@Ken Miller I don't agree. The video directly shows ID-creationists speaking specifically about "DNA that doesn't code for proteins". If they want to change their tune and make clarifications to ONLY be about DNA that isn't transcribed either, then let them. There are good responses to those clarifications too (as you mention), but this video is a perfectly good response to what Jonathan Wells and Douglas Axe are on video saying.
John, I didn't think I was complaining. I was pointing out that there are much more effective responses to the creationist distortions, and the Britten-Davidson model is a great example. Remember the title of the podcast: "Biologists thought all non-coding DNA was junk." Please note that the genes for tRNAs and rRNAs are NOT non-coding, and that was the point of my comment. :-)
Ken Miller says, "Please note that the genes for tRNAs and rRNAs are NOT non-coding ..."
Really? There are two types of genes, protein-coding genes and non-coding genes. The genes for tRNA and rRNA are non-coding genes. Do you (Ken) think I should edit the Wikipedia articles that Mikkel and I worked on?
https://en.wikipedia.org/wiki/Non-coding_DNA
https://en.wikipedia.org/wiki/Non-coding_RNA
https://en.wikipedia.org/wiki/Junk_DNA
Do you think I should change the definitions in my book?
I agree that Daniel Stern Cardinale could have given other examples of functional non-coding DNAs that were known in 1970 but I don't think there's any reason to criticize the example he picked.
I'd also like to point out that it's not only creationists who make this mistake. The scientific literature is full of similar false statements saying that people like Francis Crick, Thomas Jukes, Sydney Brenner and others once though that all non-coding DNA was junk.
No, of course not. If "non-coding" is understood as DNA that does not code for mRNAs that specify an amino acid sequence then rRNA and tRNA genes clearly qualify. No argument there. My point was by only citing the discovery of tRNA back in 1958 it becomes pretty easy for creationists to shrug and say that's not what anyone ever meant by "junk DNA." I just thought there were better examples that would make a stronger case.
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I'm sorry, Larry, but as a response to creationist distortions with respect to "junk DNA," this YouTube video is pretty weak stuff. The evidence it cites are some of the early papers regarding tRNA sequences. While it's true that tRNA sequences (and rRNA sequences) are never translated into protein, these are certainly not what the creationists refer to when they attack the concept of junk DNA. We routinely refer to these as "genes," and the label is appropriate. What the video blogger has focused on is the (mistaken) notion that the only functional DNA sequences are those that code for proteins. That's really just a poor choice of words by the creationists, who could easily respond by a "clarification" that they actually meant was DNA that is not transcribed into one of the forms of RNA used to synthesize proteins. At a stroke, that covers mRNA, tRNA, and rRNA. A much better rebuttal would focus on the longstanding understanding that much of DNA (relating to the c-Value Paradox) could be understood as regulatory and control elements (Think the Britten-Davidson model). That model made it clear that many of the highly repetitive sequences in DNA could be explained in terms of gene regulation. Regulatory sequences are clearly not "junk," and that's been understood at least since the 1960s. (Ken Miller)
@Ken Miller
I don't agree. The video directly shows ID-creationists speaking specifically about "DNA that doesn't code for proteins". If they want to change their tune and make clarifications to ONLY be about DNA that isn't transcribed either, then let them. There are good responses to those clarifications too (as you mention), but this video is a perfectly good response to what Jonathan Wells and Douglas Axe are on video saying.
As far as junk DNA goes, it's a minor point, but it's one worth making. Why complain?
John, I didn't think I was complaining. I was pointing out that there are much more effective responses to the creationist distortions, and the Britten-Davidson model is a great example. Remember the title of the podcast: "Biologists thought all non-coding DNA was junk." Please note that the genes for tRNAs and rRNAs are NOT non-coding, and that was the point of my comment. :-)
Ken Miller says, "Please note that the genes for tRNAs and rRNAs are NOT non-coding ..."
Really? There are two types of genes, protein-coding genes and non-coding genes. The genes for tRNA and rRNA are non-coding genes. Do you (Ken) think I should edit the Wikipedia articles that Mikkel and I worked on?
https://en.wikipedia.org/wiki/Non-coding_DNA
https://en.wikipedia.org/wiki/Non-coding_RNA
https://en.wikipedia.org/wiki/Junk_DNA
Do you think I should change the definitions in my book?
I agree that Daniel Stern Cardinale could have given other examples of functional non-coding DNAs that were known in 1970 but I don't think there's any reason to criticize the example he picked.
I'd also like to point out that it's not only creationists who make this mistake. The scientific literature is full of similar false statements saying that people like Francis Crick, Thomas Jukes, Sydney Brenner and others once though that all non-coding DNA was junk.
No, of course not. If "non-coding" is understood as DNA that does not code for mRNAs that specify an amino acid sequence then rRNA and tRNA genes clearly qualify. No argument there. My point was by only citing the discovery of tRNA back in 1958 it becomes pretty easy for creationists to shrug and say that's not what anyone ever meant by "junk DNA." I just thought there were better examples that would make a stronger case.
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