If one studies a genome sequence and comes across a region that is of the length and arrangement of a protein-encoding gene, and is enclosed but not interrupted by start and stop codons, then one can reasonably infer that this sequence is likely to be functional, even if no other evidence is yet in [...]
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Matt Ridley, author of such books as The Red Queen, Genome, and The Origins of Virtue (and not to be confused with biologist Mark Ridley), asks the question “Will we clone a dinosaur?” in Time Magazine. His answer, at least in terms of the Jurassic Park sense of cloning a dinosaur from ancient DNA, [...] Anyone who reads this blog but not Sandwalk (if any) should go right now and see Larry’s posts on junk DNA. Although I do not care so much for the term “junk DNA” because often it is employed ambiguously, Larry is careful to define it explicitly as sequences for which the evidence indicates nonfunction. [...] Note – this post has been updated since originally posted. In the recent exchange regarding my post about genome size and code bloat, one of the authors of the study in question made the following claim: In its conclusion prof. Gregory suggests that we claim that “Non-coding DNA doesaccumulate “so that” it will result [...] Over on his blog, Greg Laden points to some new work by John Mattick’s group on non-coding RNA expression in mouse brains. It’s interesting stuff, and worth a look. Please bear in mind as you do, however, that non-protein-coding but functional RNA is nothing new. Ribosomes are made of non-coding RNA, for one thing. [...] Just a reminder, these are the important points under discussion: * Proponents of ID themselves clearly suggest that “junk DNA” will mostly or all be functional. * No unambiguous explanation has been given for why ID must assume that non-coding DNA is functional, especially since they say nothing can be known about the designer [...] I first became interested in genome size because of its tie-ins with important evolutionary questions in which I was (and still am) interested, such as punctuated vs. gradual patterns, levels of selection, and adaptive vs. non-adaptive processes. What I didn’t realize was that one component of the question, the quantity of DNA that is [...] I recently did an interview with New Scientist for what, I am happy to say, was one of the most reasonable popular reviews of “junk DNA” that has appeared in recent times (Pearson 2007). My small section appeared in a box entitled “Survival of the fattest”, in which most of the discussion related to [...] I have a request that I hope some readers can help me with. I am looking for examples from the literature (rather than any “general sense”) of people who claimed that “junk DNA” or “selfish DNA” was totally non-functional. I am particularly interested in peer-reviewed primary articles, but media reports and textbooks are of [...] There has been a lot of discussion regarding discoveries in genomics, in terms of both genes (especially their number) and non-coding DNA (in particular whether any of it is functional and how much of it is transcribed). All of this supposedly contradicts long-held assumptions about genomes, especially those attributed to the early proponents of [...] |
T. Ryan Gregory 
I am an evolutionary biologist specializing in genome size evolution at the University of Guelph in Canada.
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