Nils Reinton has just posted a provocative piece on Sciphu entitled Hammering nails in the “junk-DNA” coffin. Here's what he says,Below you will find a list of references that I hope will contribute to the fall of the term “junk-DNA“, - some of it may (currently) lack a known function, but it is not junk !!!You are more than welcome to visit Sciphu and make comments. I can't be bothered.
Disclaimer: This is a list of useful references when arguing against the common overestimation of the amount of “junk”-DNA. By listing these I am not claiming anything beyond what I have already posted on this blog or in a comment somewhere. Also and importantly, I have not myself had the time to review these articles as thoroughly as I would have wanted to, - some have been read carefully, others lightly and yet others just skimmed through. Thus, you are more than welcome to comment on these references if you have opinions on any of them, or find them unsuited for this list.
The articles are just the same-old, same-old, litany of occasional discoveries of functional bits of DNA coupled with a fanatical belief in the biological significance of every single transcript that has ever been reported in the literature.
Oh yes, I almost forgot. Nils also throws in some papers about the number of binding sites for transcription factors. I guess he hasn't read any of my postings on the importance of non-specific binding [see Transcription Factors Bind Thousands of Active and Inactive Regions in the Drosophila Blastoderm].
THEME
Genomes & Junk DNA
Total Junk so far
54%
I think there's good reason to assume that up to 90% of our genomes consist of junk DNA where the word "junk" means that it does not have a biological function. I haven't been able to keep up my series of postings analyzing the human genome but so far there's very good reason to believe that more than half is junk.
I've never seen an anti-junkie address the genetic load argument. Has anyone else? I wonder how they think we can survive if a substantial amount of our DNA is essential?
I think the best way to define junk DNA is to say that junk DNA has no selective constraints. This definition doesn't make us need to prove that the junk DNA has no function but only that the DNA has no function with a selective advantage.
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