I have some quick questions for the scientists, journalists, and neither-nors who read Genomicron. Should scientists nit-pick inaccuracies in news reports? Does it do any good to keep journalism on track, or is it a waste of time (or maybe even irritating)? What else can we do to improve the accuracy of science reporting, in particular involving cooperation with rather than criticism of science writers? Since I don’t have the answers yet, I will just go ahead with a snarky post in the meantime.
Here is what triggered this query. I was reading this story, How Neutral Genetic Drift Shaped Our Genome, at Scientific Blogging (based on a Johns Hopkins press office release), when I came upon this gem:
When they expanded their study across the whole human genome, they found more than 1200 such pieces of mitochondrial DNA of various lengths [nuclear pseudogenes of mitochondrial origin, or numts] embedded into chromosomes. While chimps have a comparable number, mice and rats only have around 600 numts. Since they increase in frequency as species advance, it suggested there was some evolutionary purpose to keeping them around.
Strikingly, however, none of these numts contained the blueprint (an actual gene) to make a protein that does anything, nor did they seem to control the function of any nearby genes. “At best, it seems numts are a neutral part of our genome,” says Katsanis. “If anything, they may be mildly negative since long repeat sequences can be unstable or get inserted inside genes and disrupt them.”
Ok, the nit-picker in me really wants to point out that evolution is not a process under which “species advance”, that there is no such thing as an “evolutionary purpose”, that genes are not blueprints, that this study deals with a tiny fraction of the genome, that the idea that “they accumulate steadily” makes no sense in terms of either function or neutrality given what they just said about rodents versus primates, and that of course these pseudogenes — of mitochondrial descent, no less — do not encode a functional protein by definition. There is absolutely nothing surprising in the observation that they evolve neutrally in the nuclear genome.
To Larry Moran’s recent post Stop the Press!!! … Genes Have Regulatory Sequences!, we can add Pseudogenes do not encode functional proteins! Next: DNA includes both protein-coding genes and non-coding sequence!
(Update: Scientific Blogging redeems itself with a good post about the ENCODE hype here)
(Another update: Evolution Diary uncritically posts the same nonsensical press release here.)
(Another update: The paper itself is actually far more interesting than this poorly crafted press release would make it appear. See the open access pdf here.)