Not to harp on Uncommon Descent today, but their seeming inability to see words that they don’t like gives the appearance of no reading comprehension skills whatsoever. Take for example their read of this New Scientist article on cute little marsupials.
Let’s first quote from the article:
From the genome sequences of placental mammals such as humans, mice and chimpanzees, the researchers identified a set of sequences that are relatively unchanged (conserved) in all placental mammals and are therefore likely to be of some functional significance.
About one-third of these sequences lay within genes, and the rest were in noncoding regions that presumably help regulate the activity of genes.
The team then analysed the opossum genome to see if any of these sequences were unique to placentals – representing evolutionary innovations that arose after the lineages diverged.
Just 1.1% of the conserved sequences within genes were unique to placentals, they found. In contrast, a massive 20.5% of the noncoding sequences were unique to placental mammals. “Evolution is tinkering much more with the controls than with the genes themselves,” says Eric Lander of the Broad Institute in Cambridge, Massachusetts, who was one of the leaders of the consortium.
What they’re saying, is that if you take the subset of the genomes of placental mammals that is conserved across many placental species you find a certain portion of this DNA is in the coding regions – those regions which specify the sequence of transcripts that make proteins – and the larger portion is in the regions upstream of genes that control expression – promoters, transposons etc. Interestingly, in this limited subset of conserved DNA the coding regions are highly similar between placental mammals and marsupials, but it’s the control regions that show the most divergence. In other words, the difference between a mouse and a short-tailed opossum isn’t in the protein encoding sequences, so much as what controls the timing, levels, locations etc., of expression of those proteins.
Now the ID take:
In a new article in this week’s New Scientist magazine, the marsupial and placental genomes are compared. Only a meager 1.1% of the “coding” (coding for “genes”) portion of the placental genome is “unique”, while a whopping 20.5% of the “non-coding” (so-called ‘junk’ DNA) was unique to placental mammals. This indicates that where marsupials and placental mammals are genetically different is almost entirely to be found in the “junk DNA” sections of the genome.
Ummm. No. The entire genomes were not compared, just the regions that were conserved across multiple placental mammals were compared to similar regions in the marsupials. Very different pal. Once again the ID folks are trying to suggest that the so-called “junk” DNA has so many more functions that they predicted when we poor scientists were being materialist Darwinist bigots and couldn’t see that non-coding regions of DNA had function due to our unmitigated hatred for (the Christian) god. This claim is silly of course. Scientists were studying transposons for decades, their extent in the human genome wasn’t appreciated very well until results of the Human Genome Project started coming out in the last 5-10 years. We were studying promoters actively in the 1980s, long before the unpublished letter the ID creationists claim “predicted” junk DNA function wasn’t published. Again and again I’m reminded of the fly on the axle-tree, what a dust do they raise!
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