John Mattick and Jonathan Wells both believe that most of the DNA in our genome is functional. They do not believe that most of it is junk.
John Mattick and Jonathan Wells use the same arguments in defense of their position and they quote one another. Both of them misrepresent the history of the junk DNA debate and both of them use an incorrect version of the Central Dogma of Molecular Biology to make a case for the stupidity of scientists. Neither of them understand the basic biochemistry of DNA binding proteins leading them to misinterpret low level transcription as functional. Jonathan Wells and John Mattick ignore much of the scientific evidence in favor of junk DNA. They don't understand the significance of the so-called "C-Value Paradox" and they don't understand genetic load. Both of them claim that junk DNA is based on ignorance.
Dan Graur has a recent post on the phylogeny of placental mammals [The Root of the Placental Phylogenetic Tree: Are we Overlooking Something?]. He refers to a recent review in Molecular Biology and Evolution (MBE) that discusses various options. Graur believes that the question has been settled by examining transposon insertions.
But that's not the part that caught my attention. At the end of his post he says,
Finally, there is a small sentence in the Teeling and Hedges commentary that drove me up the wall: “The timing of the splitting event—approximately 100 Ma based on molecular clocks—is not in debate, at least among molecular evolutionists (Hedges et al. 1996…” Actually, dear Blair, it is. And whether you like it or not, both William Martin and I are fine molecular evolutionists.
The reference is to a paper by Dan Graur and Bill Martin—a formidable team that you want on your side because the alternative can be very embarrassing. You really, really don't want to mess with these guys.
We need more papers like this one.
Graur, D. & Martin, W. (2004) Reading the entrails of chickens: molecular timescales of evolution and the illusion of precision. TRENDS in Genetics 20:80-86 [doi: 10.1016/j.tig.2003.12.003] [PDF]
The enzyme L-glucono-γ-lactone oxidase is required for the synthesis of vitamin C. Humans cannot make this enzyme because the gene for this enzyme is defective [see Human GULOP Pseudogene]. The GenBank entry for this pseudogene is GeneID=2989. GULOP is located on chromosome 8 at p21.1 in a region that is rich in genes.
Here's a diagram that compares what is left of the human GULOP pseudogene with the functional gene in the rat genome.
Jerry Coyne thinks that the Beatles are the greatest rock group ever [Match this song!]. I'm pleased to announce that I agree with him on this point.
Jerry thinks that A Day in the Life is the best Beatles' song and that's where we part company. His second choice is Eleanor Rigby [Eleanor Rigby] and that's also one of my top ten.
We'll see what his other favorites are over the next few days. If he doesn't mention the very best song (IMHO) I'll correct him when he's finished. 
Here's a short quiz for proponents of Intelligent Design Creationism. Let's see if you have been paying attention to real science. Please try to answer the questions below. Supporters of evolution should refrain from answering for a few days in order to give the creationists a chance to demonstrate their knowledge of biology and of evolution.
The bloggers at Evolution News & Views (sic) are promoting another creationist book [see Biological Information]. This time it's a collection of papers from a gathering of creationists held in 2011. The title of the book, Biological Information: New Perspectives suggests that these creationists have learned something new about biochemistry and molecular biology.
One of the papers is by Jonathan Wells: Not Junk After All: Non-Protein-Coding DNA Carries Extensive Biological Information. Here's part of the opening paragraphs.
James Watson and Francis Crick’s 1953 discovery that DNA consists of two complementary strands suggested a possible copying mechanism for Mendel’s genes [1,2]. In 1958, Crick argued that “the main function of the genetic material” is to control the synthesis of proteins. According to the “ Sequence Hypothesis,” Crick wrote that the specificity of a segment of DNA “is expressed solely by the sequence of bases,” and “this sequence is a (simple) code for the amino acid sequence of a particular protein.” Crick further proposed that DNA controls protein synthesis through the intermediary of RNA, arguing that “the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid, is impossible.” Under some circumstances RNA might transfer sequence information to DNA, but the order of causation is normally “DNA makes RNA makes protein.” Crick called this the “ Central Dogma” of molecular biology [3], and it is sometimes stated more generally as “DNA makes RNA makes protein makes us.”
The Sequence Hypothesis and the Central Dogma imply that only protein-coding DNA matters to the organism. Yet by 1970 biologists already knew that much of our DNA does not code for proteins. In fact, less than 2% of human DNA is protein-coding. Although some people suggested that non-protein-coding DNA might help to regulate gene expression, the dominant view was that non-protein-coding regions had no function. In 1972, biologist Susumu Ohno published an article wondering why there is “so much ‘ junk’ DNA in our genome” [4].
- Crick published a Nature paper on The Central Dogma of Molecular Biology in 1970. Did he and most other molecular biologists actually believe that "only protein-coding DNA matters to the organism?"
- Did Crick really say that "DNA makes RNA makes protein" is the Central Dogma or did he say that this was the Sequence Hypothesis? Read the paper to get the answer—the link is below).
- Is it true that, in 1970, the majority of molecular biologists did not believe in repressor and activator binding sites (regulatory DNA)?
- Is it true that in 1970 molecular biologists knew nothing about the functional importance of non-transcribed DNA sequences such as centromeres and origins of DNA replication?
- It is true that most molecular biologists in 1970 had never heard of genes for ribosomal RNAs and tRNAs (non-protein-coding genes)?
- If the answer to any of those questions contradicts what Jonathan Wells is saying then why do you suppose he said it?
Crick, F. (1970) Central Dogma of Molecular Biology. Nature 227:561-563. [PDF]
We've been in Copenhagen for a few days but today is the last day of our vacation. We fly to Iceland and Toronto in a few hours.
Here are some photos of Saint Petersburg. I was happy to visit the cruiser Aurora in the Neva river. I first read about its role in the Russian revolution when I was in high school.
The fourth photo shows a typical street scene in the city. You should be able to translate the sign (СТОП) under the stop lights if you were paying attention to my post from a few weeks ago.
The highlight of our Baltic cruise was the visit to Saint Petersburg, Russia. We hired a guide and driver to take us around to the various sites in Saint Petersburg and the outskirts. The Hermitage (Зрмитаж) museum is located on the banks of one of the main channels of the Neva river (Болъшая Нева). The first photo shows a view form across the river.
This is the old winter palace of the Russian Czars so the building itself is part of the history—like the Louvre in Paris.
The second photo is one of the spectacular views from inside the museum. Everyone says that you really need three days to see everything and I agree. However, our guide took us on a brief tour of the major highlights so we got a good impression in just three hours.
The last photo shows us getting into our van at the end of the visit. If you look closely, you’ll see the name of Ms. Sandwalk’s blog on the dashboard (click to embiggen).
We visited Helsinki, Finland, a few days ago (August 14, 2013). It was a rainy day. We spent most of our time shopping and walking around the old town.
We visited Stockholm yesterday and toured the city with my cousin Sharon and her husband Dennis. (That’s them with Ms. Sandwalk in the third photo.) Here are some photos of the Old Town including one of the Swedish Academy where I tried to put in a good word for all my readers.
We're celebrating our 45th wedding anniversary by taking a cruise in the Baltic. We were in Oslo, Norway on our anniversary day (August 9) where we met our friends Dag and Robin from graduate student days. They are als0 marride 45 years so we celebrated with champagne at their house. More about that later.
The University of Rostock was founded in 1419. It’s said to be the oldest university in the Baltic Sea area. The main university building is a prominent landmark in Rostock but I was more interested in the Zoology building off to the side.
Looks like I just missed an important conference. Does everyone know who Willi Hennig is?
Yesterday our boat stopped at the habor in Warnemünde, Germany. There was a lot of activity of the quay in Warnemünde because a number of tall ships were in the harbor.
We took the train to the medieval town of Rostock—a key port in the Hansiatic League (Hansa=guilds). The architecture was similar to that in other leading cities of the Hansiatic League, notably Bruges.
We've been on this boat for three days and we'll be on it for another 8 days as we cruise the Baltic Sea. Internet access costs 70 cents ($0.75 US) per minute so posts will be short and infrequent.
We were in Copenhagen a few days ago. Here are some pictures of the canals.
