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Tuesday, July 29, 2014

Walter Gehring (1939 - 2014)

I just learned today that Walter Gehring died in a car accident in Greece on May 29th. I learned of his death from the obituary by Michael Levine in Science [Walter Gehring (1939–2014)]. There's another obituary on the Biozentrum (Basel, Switzerland) website [Obituary for Walter Gehring (1939 – 2014)]. He was only seven years older than me.

I first met Walter Gerhing when I was a post-doc in Alfred Tissières lab in Geneva (Switzerland) in the mid-1070s. The two labs collaborated on cloning and characterizing the major heat shock gene (Hsp70) of Drosophila melanogaster. Paul Schedl and Spyros Artavanis-Tsakonis made the library in Gehring's lab in 1976-1977 and Marc-Edouard Mirault and I isolated the mRNA for screening and then identified the genes we cloned. The result was three papers in Cell (see below). (John Lis, then in David Hogness' lab, was cloning the same gene.)

I met Gerhing dozens of times but I only had a few conversations with him one-on-one. We always talked about evolution. I always found him to be very charming and very curious and not embarrassed to admit that he didn't know something. Other post-docs and students in his lab have different impressions.

As Michael Levine puts it ...
An amazing group of students and postdocs was attracted to the Gehring lab over the years: Eric Wieschaus (Nobelist), Christianne Nüsslein-Volhard (Nobelist), David Ish-Horowicz, Spyros Artavanis-Tsakonas, Paul Schedl, Alex Schier, Georg Halder, Hugo Bellen, and Markus Affolter, to mention just a few. I worked closely with two of my future lifelong friends and colleagues: Ernst Hafen and Bill McGinnis. The lab was an absolute blast, but a strange mix of anarchy and oppression. Walter permitted considerable independence, but was hardly laissez-faire. He could be confrontational, and did not hesitate to call us out (particularly me) when he felt we were misbehaving.

I found Walter to be a complicated character. He had the mannerisms of an authoritative Herr Doktor Professor, but was also folksy and unaffected and always ready to laugh and joke. He sometimes felt competitive with his students and postdocs, but was also highly supportive and proud of our independent careers. In short, I believe the key to Walter's success was his yin and yang embodiment of old-world scholar and modern competitive scientist. He was able to exude charm and empathy, but nothing we did seemed to be quite good enough. In other words, tough love, possibly the perfect prescription for eliciting the very best efforts from his students and postdocs.
Walter Gehring was one of a small group people who changed the way I think about science.


Artavanis-Tsakonas, S., Schedl, P., Mirault, M.-E., Moran, L. and J. Lis (1979) Genes for the 70,000 dalton heat shock protein in two cloned D. melanogaster DNA segments. Cell 17, 9-18. [doi: 10.1016/0092-8674(79)90290-3]

Moran, L., Mirault, M.-E., Tissières, A., Lis, J., Schedl, P., Artavanis-Tsakonas, S. and W.J. Gehring (1979) Physical map of two D. melanogaster DNA segments containing sequences coding for the 70,000 dalton heat shock protein. Cell 17, 1-8. [doi: 10.1016/0092-8674(79)90289-7]

Schedl, P., Artavanis-Tsakonas, S., Steward, R., Gehring, W. J., Mirault, M.-E., Goldschmidt-Clermont, M., Moran, L. and A. Tissières (1978) Two hybrid plasmids with D. melanogaster DNA sequences complementary to mRNA coding for the major heat shock protein. Cell 14, 921-929. [doi: 10.1016/0092-8674(78)90346-X]

Monday, July 28, 2014

How many genes do we have and what happened to the orphans?

How many genes in the human genome? There's only one correct answer to that question and that's "we don't know."

The main problem is counting the number of genes that produce functional RNA molecules. The latest Ensembl results are based on build CRch37 from February 2009 and the GENCODE annotation from last year (GENCODE 19) [see Human assembly and gene annotation and Harrow et al., 2014]

The most recent estimates are 20,807 protein-encoding genes, 9,096 genes for short RNAs, and 13,870 genes for long RNAs. This gives 43,773 genes. Nobody knows for sure how many of the putative genes for RNAs actually exist. They may only be a few thousand functional genes in this category.

It's a lot easier to figure out whether a gene really encodes a functional protein so most of the annotation effort is focused on those genes. I want to draw your attention to a recent paper by Ezkurdia et al. (2014) that discusses this issue. The authors begin with a bit of history ...

Transcription Initiation Sites: Do You Think This Is Reasonable? (revisited)

I'm curious about how different people read the scientific literature. My way of thinking about science is to mentally construct a model of how I think things work. The more I know about a subject, the more sophisticated the model becomes.

When I read a new paper I immediately test it against my model of how things are supposed to work. If the conclusions of the paper don't fit with my views, I tend to be very skeptical of the paper. Of course I realize that my model could be wrong and I'm always on the lookout for new results that challenge the current dogma, but, in most cases, if the paper conflicts with current ideas then it's probably flawed.

This is what people mean when they talk about making sense of biology. The ENCODE papers don't make sense, according to my model of how genomes work so I was immediately skeptical of the reported claims. The arseniclife paper conflicted with my understanding of the structure of DNA and how it evolved so I knew it was wrong even before Rosie Redfield pointed out the flaws in the methodology.

Finding the "perfect" enzyme

I got an email message yesterday from a student who is taking a summer course in biochemistry. His professor asked the class to find "most efficient enzyme known to man." The professor gave them a hint by telling them that the enzyme had something to do with nucleotide biosynthesis. The student contacted me because some of my blog posts popped up on Goggle. He (the student) was a bit confused about how to define the "perfect" enzyme.

There are two different ways of defining the "perfect" enzyme and both of them are wrong because there's no such thing. The common textbook definition picks up on the idea that the "perfect" enzyme catalyzes a reaction every time it encounters a substrate(s). These enzyme rates are referred to as "diffusion-controlled" rates since the rate is limited only by the rate at which substrate diffuses into the reaction site on the enzyme. Some enzymes can even catalyze reactions that are slightly faster than the diffusion-controlled limit.

Here's what Voet & Voet (4th edition) say (page 490) ...

Friday, July 25, 2014

The Central Dogma according to Riken

You may never have heard of Riken. Here's what they say on their website [Riken] ...
RIKEN is Japan's largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.
They've published a video on the Central Dogma. Here's how they describe it ...
The 'Central Dogma' of molecular biology is that 'DNA makes RNA makes protein'. This anime shows how molecular machines transcribe the genes in the DNA of every cell into portable RNA messages, how those messenger RNA are modified and exported from the nucleus, and finally how the RNA code is read to build proteins.

The video was made by RIKEN Omics Science Center (RIKEN OSC) for the exhibition titled 'Beyond DNA' held at National Science Museum of Japan. RIKEN OSC has published in Nature Genetics on the regulation of RNA expression in human cancer cells.
Most of you know that I have a different view of The Central Dogma of Molecular Biology but that's not what I want to discuss here. Watch the video. Do you think it's a good idea to show this process as well-designed little machines and ships? It sure gets the IDiots excited {RIKEN’s 10-minute antidote to atheism: see for yourself].



Wednesday, July 02, 2014

Carnival of Evolution #73: World Cup Edition

This month's Carnival of Evolution is hosted by none other than the King of the Carnival, Bjørn Østman Pleiotropy . Read it at 73rd Carnival of Evolution: World Cup Edition .
Welcome to the 2014 Carnival of Evolution World Cup of evolution blog posts.

We have an exciting post ahead of us today where we will find the winner of the inaugural CoE World Cup. Entered posts will be scored based on several parameters, and matches will be determined probabilistically.

The scoring system works like this:

+1 for mentioning "evolution" or "evolve"
+1 for posts about biological evolution
-1 for saying "develop" or "development" when meaning "evolve" or "evolution"
-1 for being very short
-2 for being very long
0 to +5 points based on the interest of the referee (the CoE host)
+2 for posts about peer-reviewed articles
+4 for posts whose authors clearly present opinions of their own
+1 per picture (up to three) included in the post
+1 for attracting any comments
+1 extra for each original picture (max 3)
+3 for showing videos
+25 for reports on rabbit fossils from the Cambrian
-5 for any hint of panadaptationism
-2 for each logical fallacy
-4 for any mention of aquatic ape theory
-7 for agreeing with Lynn Margulis that everything is endosymbiosis
-3 if talking about the work of others without citation
-5 to -1 for any wrong statements about evolution - See more at: http://pleiotropy.fieldofscience.com/2014/07/73rd-carnival-of-evolution-world-cup.html#sthash.75w1XHA6.dpuf
It was a tough battle. My own entry, The Function Wars: Part I, had a fairly low score but managed to squeak out a victory in the early rounds in spite of the fact that it had a severe disadvantage (too long).

My post beat out Was Fisher (W)right? in the semi-final thanks to an own goal in extra time. In the final, Function Wars was up against a better post Of Population Structure and the Adaptive Landscapes but Function Wars won on penalty kicks. Yeah!!!!

If you want to host a Carnival of Evolution please contact Bjørn Østman. Bjørn is always looking for someone to host the Carnival of Evolution. He would prefer someone who has not hosted before but repeat hosts are more than welcome right now! Bjørn is threatening to name YOU as host even if you don't volunteer! Contact him at the Carnival of Evolution blog. You can send articles directly to him or you can submit your articles at Carnival of Evolution although you now have to register to post a submission. Please alert Bjørn or the upcoming host if you see an article that should be included in next month's. You don't have to be the author to nominate a post.

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Tuesday, July 01, 2014

The Function Wars: Part II

This is Part II of several "Function Wars"1 posts. The first one is on Quibbling about the meaning of the word "function" [The Function Wars: Part I].

The ENCODE legacy

I addressed the meaning of "function" in Part I It is apparent that philosophers and scientists are a long way from agreeing on an acceptable definition. There has been a mini-explosion of papers on this topic in the past few years, stimulated by the ENCODE Consortium publicity campaign where the ENCODE leaders clearly picked a silly definition of "function" in order to attract attention.

Unfortunately, the responses to this mistake have not clarified the issue at all. Indeed, some philosophers have even defended the ENCODE Consortium definition (Germain et al., 2014). Some have opposed the ENCODE definition but come under attack from other scientists and philosophers for using the wrong definition (see Elliott et al, 2014). The net effect has been to lend credence to the ENCODE Consortium’s definition, if only because it becomes one of many viable alternatives.

Saturday, June 28, 2014

Ann Gauger's old facts

Some of you are probably watching Saturday morning cartoons but for those of you looking for other forms of entertainment I offer a list of six "old facts" that Ann Gauger says have been proven to be wrong [Why Does Biology Still Have the Ability to Surprise Us?].

Since I'm at least as old as Ann Gauger, I offer my own interpretation under each one. If you want to see how she interprets them you'll have to go to the IDiot website.

1. Old fact: DNA is stable and genes don't hop around.
I suppose there was a time when scientists might have thought that "DNA was stable." I was taught about "jumping genes" in my second year genetics class in 1965. I think that's before many of you were born so it's a pretty old fact.
2. New "old" fact: Mobile genetic elements are selfish DNA that replicate themselves without benefit to the organism, thus cluttering the genome with garbage.
That's still pretty much true today.
3. Old fact: A gene is an uninterrupted stretch of DNA that encodes a single protein. Genes are arranged like beads on a string.
I learned in 1965 that some genes produced tRNA and ribosomal RNA. I learned in 1975 that some protein-encoding genes had introns. (That one was a surprise.) I still think that genes are lined up one-after-another on their chromosomes although there are some minor exceptions. I learned about overlapping genes, for example, when the φX174 genome was sequenced in 1978. That's how old her facts are.
4. Old fact: There are only 3 forms of RNA: messenger RNA, transfer RNA, and ribosomal RNA.
Scientists have known about RNA viruses for at least 70 years. That's long before the discovery of messenger RNA and tRNA. It wasn't until the early 1970s that molecular biologists became aware of regulatory RNAs, RNA primers on Okazaki fragments, and antisense RNAs. This was followed quickly by the discovery of many other types of RNAs. Ann Gauger says these are "new" discoveries. I guess that depends on whether something that's been known for forty years (or seventy years) counts as "new."
5. Old fact: Pseudogenes are useless broken remnants of former genes.
Still true today. The fact that some of the sequence of one-in-a-million pseudogenes may have secondarily acquired another function doesn't change the fact that it is a pseudogene.
6. Old fact: The genome is full of junk, the remnants of wasteful evolutionary processes and selfish DNA (see #1, #2 and #5 above).
Still a fact in the 21st century.

Friday, June 27, 2014

This is my little boy playing in the mud

My son, Gordon, ran in a 19km race at Whistler (British Columbia) last weekend. There were lots of obstacles and a 10,000 volt electric shock at the end. He said it was "Super fun!"

I remember when playing in the mud meant something a lot different.


UPDATE Ms. Sandwalk has posted more pictures, and more words at: Oh My Goodness.


Wednesday, June 25, 2014

The Function Wars: Part I

This is Part I of the "Function Wars: posts. The second one is on The ENCODE legacy.1

Quibbling about the meaning of the word "function"

The world is not inhabited exclusively by fools and when a subject arouses intense interest and debate, as this one has, something other than semantics is usually at stake.
Stephan Jay Gould (1982)
The ENCODE Consortium tried to redefine the word “function” to include any biological activity that they could detect using their genome-wide assays. This was not helpful since it included a huge number of sites and sequences that result from spurious (nonfunctional) binding of transcription factors or accidental transcription of random DNA sequences to make junk RNA [see What did the ENCODE Consortium say in 2012?]..

I believe that this strange way of redefining biological function was a deliberate attempt to discredit junk DNA. It was quite successful since much of the popular press interpreted the ENCODE results as refuting or disproving junk DNA. I believe that the leaders of the ENCODE Consortium knew what they were doing when they decided to hype their results by announcing that 80% of the human genome is functional [see The Story of You: Encode and the human genome – video, Science Writes Eulogy for Junk DNA]..

The ENCODE Project, today, announces that most of what was previously considered as 'junk DNA' in the human genome is actually functional. The ENCODE Project has found that 80 per cent of the human genome sequence is linked to biological function.

[Google Earth of Biomedical Research]

Monday, June 16, 2014

A bun bargain

We were at our local supermarket yesterday and I wanted to buy some large Kaiser rolls. Unfortunately, the bins were empty.

I guess the customers couldn't resist the bargain if they bought half-a-dozen buns.


Friday, June 13, 2014

Ontario elects a Liberal government under Kathleen Wynne

The people of Ontario (Canada) voted in a provincial election yesterday and the Liberal Party won a majority of the seats. The leader of the party is Kathleeen Wynne and she becomes the first woman to be elected Premier of Ontario. (She has been Premier for the past sixteen months since she became leader of the Liberal Party.) Not only is she the first woman, she is the first openly gay politican to be elected Premier of any province in Canada. (According to Wikipedia, she is the first openly gay head of any government in the Commonwealth.)

The results are:

Liberals: 59 seats, 39% of the vote
Progressive Conservatives: 27 seats, 31%
New Democratic Party: 21 seats, 24%
Green Party: 0 seats, 5%.

The results are going to be poured over with a fine-tooth comb in the next few weeks but it's clear that the Tea-Party agenda of the Progressive Conservatives did not work. (He hired American Republican strategists to help with his campaign.) They should have won the election handily after 11 years of Liberal government plagued by scandal but, instead, they lost 10 seats and their leader Tim Hudak resigned last night when the results became clear.




Friday, June 06, 2014

June 6, 1944

Today is the 70th anniversary of D-Day—the day British, Canadian, and American troops landed on the beaches of Normandy.1

For baby boomers it means a day of special significance for our parents. In my case, it was my father who took part in the invasions. That's him on the right as he looked in 1944. He was an RAF pilot flying rocket firing typhoons in close support of the ground troops. During the initial days his missions were limited to quick strikes and reconnaissance since Normandy was at the limit of their range from southern England. During the second week of the invasion (June 14th) his squadron landed in Crepon, Normandy and things became very hectic from then on with several close support missions every day.

I have my father's log book and here (below) are the pages from June 1944. The red letters on June 6 say "DER TAG." It was his way of announcing D-Day. On the right it says "Followed SQN across channel. Saw hundreds of ships ... jumped by 190s. LONG AWAITED 2nd FRONT IS HERE." Later that day they shot up German vehicles south-east of Caen where there was heavy fighting by British and Canadian troops. The next few weeks saw several sorties over the allied lines. These were attack missions using rockets to shoot up German tanks, vehicles, and trains.


The photograph on the right shows a crew loading rockets onto a typhoon based just a few kilometers from the landing beaches in Normandy. You can see from the newspaper clipping in my father's log book that his squadron was especially interested in destroying German headquarter units and they almost got Rommel. It was another RAF squadron that wounded Rommel on July 17th.

The log book entry (above) for June 10th says, "Wizard show. Recco area at 2000' south west of Caen F/S Moore and self destroyed 2 flak trucks, 2 arm'd trucks, and i arm'd command vehicle, Every vehicle left burning but one. Must have been a divisional headquarters? No casualties."

Here's another description of that rocket-firing typhoon raid [Air Power Over the Normandy Beaches and Beyond].
Intelligence information from ULTRA set up a particularly effective air strike on June 10. German message traffic had given away the location of the headquarters of Panzergruppe West on June 9, and the next evening a mixed force of forty rocket-armed Typhoons and sixty-one Mitchells from 2 TAF struck at the headquarters, located in the Chateau of La Caine, killing the unit's chief of staff and many of its personnel and destroying fully 75 percent of its communications equipment as well as numerous vehicles. At a most critical point in the Normandy battle, then, the Panzer group, which served as a vital nexus between operating armored forces, was knocked out of the command, control, and communications loop; indeed, it had to return to Paris to be reconstituted before resuming its duties a month later.

My father was awarded the Distinguished Flying Cross (DFC) for his efforts during the war.



1. The British landed at Sword Beach and Gold Beache, the Canadians at Juno Beach, and American troops landed at Omaha and Utah Beaches.

Wednesday, June 04, 2014

Do you really "get" evolution?

Stephanie Keep is the new editor of Reports of the National Center for Science Education at NCSE (National Center for Science Education).

She tells an interesting story in her first post on the Science Laegue of Amercia blog [A New Finger in the Pie].
An editor friend of mine asked me the other day to read an activity she’s developing for middle school, one of the soon-to-be plethora of activities aligned to the Next Generation Science Standards. This particular one was about evolution, and asked kids to look for variation in a number of human traits and then infer adaptive explanations. For example, they could measure finger lengths and then come up with a reason that longer fingers are more adaptive than shorter ones. What followed was a half-hour conversation in which I tried my best to explain why that was a terrible idea for an activity. And here’s the thing—this friend of mine, she’s super-smart and has an advanced degree in biology from Harvard University. Now, she completely understood, once we discussed it, why that kind of activity will reinforce misconceptions about evolution (that every feature is adaptive, that you can infer a structure’s adaptive value from its current function, etc.), but we still had to have the discussion.

I have worked for the past decade-plus with scientists, science writers, and science educators, all of whom have the best intentions in the world, all of whom would have no problem declaring their allegiance to the cause of an authentic science education grounded in evolution. But—and I don’t want to point fingers at anybody here—many of them would have not batted an eye if that activity had come across their desks. And this, I believe, is one of the most important truths we have to face: many of us don’t really get evolution. It’s such a beautiful, simple, and powerful idea, but it’s also finicky, demanding vigilant attention to detail to be properly explained and explored.
Most of you will be familiar with this idea since I've been complaining about adaptationism for decades. In order to "get" evolution, you need to know about Neutral Theory and random genetic drift—and that's just for starters. We need to work much harder to dispel misconceptions about evolution.

Lot's of people don't really "get" evolution but, in fairness, they don't study it either. But if you are going to write about evolution—or teach it—then you'd better make sure you understand it. Unfortunately, there are far too many people like Stephanie Keep's friend. We have to fix that.

There's one group that spends an extraordinary amount of time "studying" evolution without ever "getting" it. I'm referring to creationists, especially the Intelligent Design Creationists, otherwise known as IDiots. They've been told time and time again that there's much more to evolution than just adaptation. Recently, some of them actually seemed to "get" the ideas of Neutral Theory and random genetic drift although that turned out to be an illusion. They still don't get evolution.

In any case, one of the creationists (Donald McLaughlin1) has blogged about Stephanie Keep's story [see A New Hire at the National Center for Science Education Admits "Many of Us Don't Really Get Evolution"]. Here's part of what McLaughlin says,
Bear in mind, too, that the very educators who don't get evolution are also the ones who fuss and complain whenever a state legislator or science standards committee member proposes language about "teaching the strengths and weaknesses" of evolution. From the way they kvetch, you would think there are no weaknesses in evolutionary theory. But if many of them don't get evolution in the first place, how would they know?

Keep says that evolution is a "beautiful, simple, and powerful idea, but it's also finicky, demanding vigilant attention to detail to be properly explained and explored." Perhaps Keep could provide a helpful list of exactly what those details are so educators like her Harvard-trained friend can stay on the straight and narrow Darwinian path, lest they join the chorus calling for a new theory of evolution.
This is ironic and confused on so many levels that I'm not even going to try and point them out. I just post it here for your amusement.


1. Here's his profile on the Discovery Institute website.
Donald McLaughlin joined Discovery Institute in August 2013, as a Development Officer and Regional Representative in the upper Midwest and Northeast regions. His areas of responsibility include cultivating and stewarding major gifts, and planned giving. Donald has had a successful career in development, including 8 years as a Regional Director of Advancement for Prison Fellowship Ministries, 2 years as National Director of Major Gifts for Teen Mania Ministries and 5 years as Regional Director of Advancement for Taylor University.

Donald is a 1975 graduate of Taylor University where he earned his BA in Speech and Drama. In 1977, he earned an MA in Clinical Audiology from Ball State University in Muncie, IN. While at Prison Fellowship, Donald also participated in the Centurions Program. Prior to his work in Development, Donald spent more than twenty years in financial services with both AG Edwards and Merrill Lynch. Donald lives in Granger Indiana, near South Bend, with his wife of 35 years, Elizabeth, who is Chair of the Communications Department at Bethel College in Mishawaka, IN. Donald enjoys reading, traveling, and music.
He also has a religious profile at: Donald McLaughlin.

Monday, June 02, 2014

"Flipping the classroom": what does that mean?

The latest issues of ASBMB Today contains an article by Brent R. Stockwell and Michael Cennamo with a provocative title: Reimagining the undergraduate science course.

It describes an undergraduate course in biochemistry at Columbia University. Apparently, this course used to be taught in a way that's similar to many biochemistry courses. The lecture consisted of PowerPoint slides and a description of basic facts such as metabolic pathways. Stockwell and Cennamo want to redesign the course to allow more time in the classroom for debate and discussion. This is an admirable goal.

They decided to "flip the classroom."
What does it mean to flip the classroom?

When we say we flipped the classroom, we mean that we had students watch recorded videos before class, freeing classroom time for discussion, group work and solving problems. But this is not something you can do overnight.

We took time to define our goals: Obviously, we wanted the students to be better prepared for each class, allowing them to engage more fully in class discussion. But we also wanted to have students put lecture material into action by tackling practical biochemistry problems.

Last summer, we had a number of meetings to design a new course that not only would get students thinking and problem solving in a new way but would provide instant feedback on how well they understood the material.
What they did was to create a video with their PowerPoint slides and a recording of the lecturer explaining what's on the slides. The students were supposed to watch the video before class and, to ensure that they did, there was a quiz at the end of the video presentation. For example, at the end of the lecture on amino acid metabolism, the students were asked to identify the product of the deamination of alanine.1

Here's the part I don't understand. What's the value of having students watch a video presentation when they have a textbook? (The recommended textbook is Lehninger, Principles of Biochemistry by David Nelson and Michael Cox (6th edition, 2013)).

Why not just assign readings from the textbook? I assume that most lecturers are not very knowledgeable about the content of most lectures in an introductory biochemistry course so they probably rely on a textbook anyway.

And what are the students supposed to do when they watch the video? In the new version of the course, students are divided into groups and they deal with problems that "required students to synthesize and apply the information from the textbook, videos and class discussion" (i.e. "problem-based learning," according to the authors). One of the question is ....
If glucose labeled with 14C at C-1 were the starting material for amino acid biosynthesis, the product(s) that would be readily formed is/are:

A. Serine labelled at alpha carbon
B. None of these
C. All of these
D. Serine labelled at the carboxyl carbon
E. Serine labelled at the R-group carbon2
I assume that the students would have to take notes while watching the video and/or download the PowerPoint slides in order to answer this question during class. Or, they could bring their textbook to class.

Do PowerPoint video presentations add anything to the course that can't be found in the textbook?

1. Pyruvate and glutamate?
2. I assume the instructors are thinking about organisms that regularly utilize glucose as a carbon source so that amino acids like serine are mostly derived from intermediates in glycolysis (e.g. humans). In that case, the students have to understand the distribution of carbon atoms in the aldolase reaction. I had to look this up to determine that the correct answer is "E." I hope I'm right. For species that use the pentose-phosphate pathway, I think the correct answer is "B." (This doesn't seem to me like a fundamental principle or concept based on an evolutionary approach to biochemistry.)

Saturday, May 31, 2014

The Third Fourth? Way

Back in 1997, James Shapiro wrote an article for the Boston Review entitled "A Third Way." It was a very confusing article. His main point seemed to be that conventional neo-Darwinism wasn't a complete picture of modern evolutionary theory.

That part wasn't news since by 1997 the ideas of Neutral Theory and random genetic drift had been around for thirty years. Apparently, Shapiro was three decades behind in his understanding of evolution.

Shapiro doesn't demonstrate that he understands population genetics and random genetic drift. This just one (of many) criticisms that I mentioned in my review of Shapiro's book Evolution: A View from the 21st Century in NCSE Reports [Evolution: A View from the 21st Century]. Shapiro responded to my review at: Reply to Laurence A Moran’s review of Evolution: A View from the 21st Century] and I discussed his response on my blog [James Shapiro Responds to My Review of His Book].

The "third" way, according to Shapiro's 1997 article, is not classic Darwinism and it's not creationism. Instead, it's a new way of looking at evolution.
What significance does an emerging interface between biology and information science hold for thinking about evolution? It opens up the possibility of addressing scientifically rather than ideologically the central issue so hotly contested by fundamentalists on both sides of the Creationist-Darwinist debate: Is there any guiding intelligence at work in the origin of species displaying exquisite adaptations that range from lambda prophage repression and the Krebs cycle through the mitotic apparatus and the eye to the immune system, mimicry, and social organization? Borrowing concepts from information science, new schools of evolutionists can begin to rephrase virtually intractable global questions in terms amenable to computer modelling and experimentation. We can speculate what some of these more manageable questions might be: How can molecular control circuits be combined to direct the expression of novel traits? Do genomes display characteristic system architectures that allow us to predict phenotypic consequences when we rearrange DNA sequence components? Do signal transduction networks contribute functional information as they regulate the action of natural genetic engineering hardware?

Questions like those above will certainly prove to be naive because we are just on the threshold of a new way of thinking about living organisms and their variations. Nonetheless, these questions serve to illustrate the potential for addressing the deep issues of evolution from a radically different scientific perspective. Novel ways of looking at longstanding problems have historically been the chief motors of scientific progress. However, the potential for new science is hard to find in the Creationist-Darwinist debate. Both sides appear to have a common interest in presenting a static view of the scientific enterprise. This is to be expected from the Creationists, who naturally refuse to recognize science's remarkable record of making more and more seemingly miraculous aspects of our world comprehensible to our understanding and accessible to our technology. But the neo-Darwinian advocates claim to be scientists, and we can legitimately expect of them a more open spirit of inquiry. Instead, they assume a defensive posture of outraged orthodoxy and assert an unassailable claim to truth, which only serves to validate the Creationists' criticism that Darwinism has become more of a faith than a science.
Now Shapiro has joined forces with some other "revolutionaries" and started a new website called "The Third Way." It has grandiose goals ....
The vast majority of people believe that there are only two alternative ways to explain the origins of biological diversity. One way is Creationism that depends upon supernatural intervention by a divine Creator. The other way is Neo-Darwinism, which has elevated Natural Selection into a unique creative force that solves all the difficult evolutionary problems. Both views are inconsistent with significant bodies of empirical evidence and have evolved into hard-line ideologies. There is a need for a more open “third way” of discussing evolutionary change based on empirical observations.
There's only one problem. I'm familiar with Shapiro's ideas and with the ideas of most of the other people listed on the website and I don't think any of them (except Eugene Koonin) have anything significant to say about evolutionary theory. Futhermore, most of them don't seem to understand that there's already been a revolution and population genetics, Neutral Theory, etc. won the day. They seem to have completely missed that revolution.

They are advocating a fourth way that skips right from adaptationism to something else.

They are like a group of would-be revolutionaries marching up Rue de Lyon in Paris only to discover that the Bastille has been replaced by an open square and an opera house.

Note: There aren't many biologists that are interested in this "Third Way" but the creationists are lapping it up [A Group of Darwin-Skeptical Scientists Seeking a "Third Way" in Biology Have Launched a New Website; Welcome to Them!].


Tuesday, May 27, 2014

Begging the Question

John Wilkins has it right: Begging that damned question.

For hundreds of years, the phrase "begging the question" meant something like "avoiding the question." It is an important fallacy in logic and philosophers should fight hard to keep the original meaning.

Unfortunately, in the past decade or so the phrase has come to mean "raising the question." That's probably because the original meaning was too subtle for the average person who preferred a much more literal interpretation of "begging the question." If you are going to use the new interpretation you should be aware of the fact that a lot of people are gong to think you're stupid.

My next post on evolving language will discuss an announcement that I hear frequently on my train. See if you can guess why it annoys me. It goes like this: "On behalf of myself and the crew I'd like to thank you for riding the train today."


Science literacy and "belief" in evolution

On May 24th 2014 Ed Yong (@edyong209) tweeted ....
Those surveys about views on evolution are a terrible guide to “science literacy” (which is itself a silly term) [Weekend update: You'd have to be science illiterate to think "belief in evolution" measures science literacy]
You can follow the Twitter thread here but it's not very enlightening.

The article that Ed Yong linked to is by Dan Kahan, a Professor of Law and a Professor of Psychology at Yale University (New Haven, Connecticut, USA). He has a B.A. from Middlebury College and a law degree (J.D.) from Harvard.

The issue that upsets Ed Yong and Dan Kahan is a serious one. It's about how one measures scientific literacy and what it means to be capable of using the scientific way of knowing to distinguish between reality and superstition. The specific issue is whether asking people if they "believe" in evolution is a valid measure of scientific literacy.

Friday, May 23, 2014

The faculty is the university

An old high school friend1 added a comment on a previous post where he alerted me to a new (for me) blog called "Piece of Mind." The author is Nassif Ghoussoub, a Professor of Mathematics at the University of British Columbia (Vancouver, Canada) and a member of the Board of Governors of that university.

His blog post is: Return on investment in faculty rarely captured by university CFOs and it makes three important points.
  1. The faculty is the university.
  2. Budget models that invest in things like $140-million in online learning while cutting normal teaching and research are unlikely to work.
  3. Cutting normal faculty positions while advocating an increase in "professional programs" and an increase in enrollment seems illogical.
I like the opening and the closing ....
"Mr. President, We are not employees of the university. We are the university."

With these words, Isidore Rabi, a distinguished faculty member at Columbia University, interrupted Dwight Eisenhower, who had started off a speech by addressing the faculty as "employees of the university." [At the time, Eisenhower was President of Columbia University.] Generation after generation of faculty members has repeated this inspirational anecdote from the early 1950s, though they know very well that their universities are increasingly becoming about everything other than the faculty. And the situation appears to be worsening. To the professional managerial class that nowadays run the neoliberal version of post-secondary education, the faculty is often seen as merely the source of the university’s problems. So, before too many of my colleagues get used to being seen as a cost, not something that provides net positive value to the university, I would like to use charter accountants’ speak to argue that investment in university research excellence could be and should be viewed as a possible driver of future revenue.

....

As to the end of the Eisenhower tale, people assumed he might have taken offense by the somewhat confrontational remark of Rabi. Instead, the latter became his closest friend on the faculty – "and when Eisenhower became President of a somewhat larger organization than Columbia, he appointed Rabi to a number of influential positions."


1. It was Bob Woodham, and I mean a high school friend from a long time ago not a high school friend who is old. None of us are "old" yet.

Thursday, May 22, 2014

The Board of Governors at the University of Saskatchewan fires President Ilene Busch-Vishniac

Last week the Provost of the University of Saskatchewan fired Robert Buckingham, Dean of Public Health, for his outspoken criticism of plans to disband his Faculty and for his public criticism of the administration for attempting to muzzle him. Buckingham was not only removed from his job as Dean but fired from his tenured position as a Professor and banned from the campus.

One week later ...
  1. Buckingham has been reinstated as a Professor in the Faculty of Public Health.
  2. The Provost, Brett Fairbairn, was forced to resign.
  3. The President, Ilene Busch-Vishniac, has been fired.
This has been a good week for universities in Canada and for the principle of academic freedom. All the major TV networks and all the major newspapers were appalled at the actions of the University of Saskatchewan. Even the Premier of Saskatchewan and the minister in charge of higher education expressed their displeasure.

Watch the CBC excerpt at: University of Saskatchewan board fires president Ilene Busch-Vishniac. It gives you a good flavor of the way this is being covered in Canada. Nobody is defending the university.

Some of the best coverage of this sorry episode is by the Star Phoenix of Saskatoon: University of Saskatchewan president Ilene Busch-Vishniac fired. According to their reporters, the Chair of the Board of Governors (Susan Milburn) announced late last night that President Busch-Vishniac has been fired "without cause." She will retain her position as a tenured Professor in the College of Engineering where presumably she will assume normal teaching and research duties.
[Susan Milburn says] "The board feels strongly that the university’s ongoing operations and its reputational rebuilding efforts will be more effective with new leadership."

The board in its statement said it had been "a painful week for the University of Saskatchewan. Many students, faculty, staff, and alumni of the U of S, and the people of the province generally, were dismayed by news emerging from the campus over the last seven days. The board was deeply troubled by this situation and committed itself to repairing the university’s reputation."

The StarPhoenix went to the president's home on the U of S campus but husband Ethan Vishniac said Busch-Vishniac would not comment.

Busch-Vishniac, who began her term at U of S on July 1, 2012, was terminated without cause, which means she is eligible to collect severance and can take up a faculty post in the university’s college of engineering.
The backdrop to this story about academic freedom is "TransformUs"—a plan to drastically cut expenses in order to meet a $45M deficit. Apparently, students and faculty at the University of Saskatchewan were not brought on board during the discussion leading up to the decision and they are not happy with a budget plan that appears to be imposed by a small number of senior administrators.

The Board of Governors has restated its support for "TransformUS" in spite of widespread protests on campus. It looks like the Board will be the next target.

Meanwhile, the faculty is upset because the Board of Governors granted the President the right to veto tenure recommendations made by peer-group tenure committees. The Faculty Association will likely take legal action against the Board because their action violates the agreement between faculty and the university. (The faculty at the University of Saskatchewan is not (yet) unionized.) (The Faculty Association is a certified union under the Trade Union Act. They have been certified since 1977.)

Stay tuned.....

This is my fifth post on this subject. The others are at ...

Tuesday, May 20, 2014

The Provost of the University of Saskatchewan has resigned

The provost of the University of Saskatchewan, Brett Fairbairn, resigned yesterday (Monday, May 20, 2014) just before an emergency meeting of the university's Board of Governors. The President of the university, Ilene Busch-Vishniac, announced that she had accepted the resignation.

Last week the Provost fired Robert Buckinham, the Dean of Public Health, from his tenured position for disagreeing with the policies of the rest of the university administration, specifically the Provost and the President. They want to disband the Faculty of Public Health and the Dean disagreed and protested the attempt to muzzle him. Two days later the President offered Buckingham a tenured position and admitted that a terrible blunder had been committed on her watch.

The Provincial Minister of Advanced Education, Rob Norris, called the emergency meeting of the Board of Governors in order to determine if recent events at the University of Saskatchewan had violated the "University of Saskatchewan Act." He spoke to the Board at their 8pm meeting then addressed the press. According to CBC News ....

Monday, May 19, 2014

Monday's Molecule #241

Last week's molecule (above) [Monday's Molecule #240] is a derivative of 2′-deoxythymidine triphosphate that's used in DNA sequencing reactions. The derivative has a 3′-O-azidomethyl group so that when this nucleotide is incorporated into a growing chain it cannot be extended because the 3′ -OH group is blocked. This is a chain-termination derivative. The large group attached to the methyl group at the C5 position on the thymine base is a color compound (a fluor). When this nucleotide is incorporated it stops chain growth, makes the DNA visible, and indicates that there's a T in the last position. The winner is James Wagstaff.

Almost all of you are familiar with today's molecule (right) although I suspect that many of you don't recognize it right away. Name the molecule—the common name will do—and briefly describe its biochemical function.

Email your answer to me at: Monday's Molecule #241. The first one with the correct answer wins. I will only post the names of winners to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Friday, May 16, 2014

The Provost and the President of the University of Saskatchewan made a mistake

The decision to fire Robert Buckingham gets more and more interesting every day. On Wednesday, the Provost fired Buckingham and told him that ...
You are to receive your final pay on May 30, 2014, as per the normal payroll cycle. You are to leave campus immediately and are not to return to your office, the School of Public Health or the university. All benefits and pension cease as of today.

Please contact ... Human Resources ... to make arrangements for the return of university equipment and your office keys, as well as to arrange a time that is appropriate to collect any remaining personal effects.
(see the letter below)

I don't care how you spin this, the Provost made a very serious error and there's no way he should continue in his job. You can help him make the honorable decision to resign by signing the petition organized by University of Saskatchewan faculty at: University of Saskatchewan: Have Brett Fairbairn, Provost of the University of Saskatchewan, Resign.

The more serious question is whether the President, Ilene Busch-Vishniac, should resign. Watch this video of her apologizing for making a mistake and taking responsibility for it: "That should never have happened.". It seems to me that this is more than just a bureaucratic slip-up.

Here's a radio interview with Robert Buckingham and Ilene Busch-Vishniac on CBC's As It Happens: University of Saskatchewan President apologizes & admits school's reputation damaged. The President says that a mistake was made but she's not worried about her job. Apparently the university will launch an investigation to see what went wrong and who is responsible. (These things usually take several months.)

It really shouldn't take more than a few seconds to see that the Provost, at least, screwed up.

Meanwhile, there seems to be a bit of confusions about what kind of an offer is being made to Buckingham. He resolutely (and correctly) defends the idea that Dean's should speak out against university policies that they disagree with.

The Saskatoon newspaper, The StarPhoenix reports that ...
(Busch-Vishniac says), ""We, frankly, blundered. That should never have happened. Tenure is certainly one of the values that every university in the world holds dear. That's as true here as is it is anywhere else and I have no excuse for what happened."

She promised that "people will be held accountable" for the decision, but did not say whether her own job is on the line. "That's for the board to decide," she said."
It's difficult to see how someone who truly believes that academic freedom is important could have made such a mistake. It sounds an awful lot like someone who didn't really believe in academic freedom but is backpedaling furiously in order to avoid being fired.

I think she should be fired because she has done enormous damage to the reputation of the University of Saskatchewan and she has lost the confidence of the faculty. She can't continue to govern under those circumstances.



Thursday, May 15, 2014

Robert Buckingham rehired at the University of Saskatchewan

Apparently, some sane person at the University of Saskatchewan had a talk with the President and informed her that she was in very deep doo-doo [see Ilene Busch-Vishniac should resign immediately as President of the University of Saskatchewan].

According to CBC News: Robert Buckingham offered tenured role at Saskatchewan university after firing.
The University of Saskatchewan said today it will offer Prof. Robert Buckingham a tenured faculty position but he won't be returning to his old job after he was fired for speaking out against the school's cuts and restructuring plans.

In a news release, the university says Buckingham won't be given back his job as head of the university's School of Public Health.

“Academic freedom and tenure are sacrosanct at the University of Saskatchewan. This case, however, is not about academic freedom," U of S president Ilene Busch-Vishniac said in the release. "Dr. Buckingham was removed from his executive director position for acting contrary to the expectations of his leadership role.”

Buckingham was fired Wednesday morning for criticizing the institution's budget cuts as part of the TransformUS restructuring plan.

“The confusion on this issue stems from differing interpretations based on his contract," Busch-Vishniac said. "Because we hold tenure in high regard, we will immediately reverse that part of our initial decision.”

Busch-Vishniac also said Buckingham was not banned from the university.
Interesting. I assume that "differing interpretations" is a euphemism for "we really screwed up and I hope this will make it go away."

Good luck with that. She admits that her decision needs to be "reversed" and that means she made a very, very, serious mistake.

The Provost should resign (or be fired) today and so should the President. We all know where the buck should stop.

Meanwhile, Lindsay Tedds has a column in today's Globe & Mail that gets it exactly right [When you're a university dean, 'toe the party line' isn't your job].
The role of a dean, such as Dr. Buckingham, is to provide leadership for and protect the integrity of their unit. Dr. Buckingham did exactly that in his criticism of the university regarding the treatment of his unit through the TransformUS process. I expect that his actions were likely met with a great deal of support from his unit, as well as from many academics across this country who wish their deans were equally courageous. In the eyes of many academics, the only ones who ‘damaged the reputation’ of the University of Saskatchewan were those complicit in attempting to censor senior academic staff and the firing of Dr. Buckingham. After all, the University of Saskatchewan is a public institution, supported by taxes and student payments. Debates regarding its management of these resources should be held openly and freely in the public sphere.


Why shouldn't you use PowerPoint slides in your classes?

Chris Buddle of McGill University (Montreal, Canada) thinks that instructors should stop putting your Powerpoint slides on-line.

He makes some excellent and powerful points but the best ones are directed at not using PowerPoint at all.
Powerpoint is so awesome! Textbook companies provide the slides and all the material is ready to go! Clickity-click-click let’s LECTURE!

Powerpoint is not awesome. Powerpoint slides are an ineffective and rather annoying tool for the University classroom. Text-heavy Powerpoint slides do not promote an active learning environment. Active learning is an important and valuable concept in higher education. Active learning means the classroom becomes a space for debate, discussion, interaction, and the instructor is the facilitator of all of this rather than a ‘voice from a podium’. Powerpoint slides can be used to illustrate concepts, for showing relevant graphs or images, but they should not be used for a long list of bulleted points. Frankly, Powerpoint often becomes a memory tool for the instructor rather than a tool for effective instruction. Try a chalkboard instead…

Students shouldn’t be forced to come to lecture – heck, they are paying for University and we are at their service. It’s their right to have access to course notes on-line.

Yes, students are paying to come to University, and instructors are paid to teach. In most cases, this means teaching in a seminar room or lecture hall. In most cases, this means teaching in a context where direct interaction with students is possible, important and a key part of the University experience! To me, it’s the student’s right to be able to go to lecture and experience an active and engaging environment: an environment that creates opportunity for learning from an expert on a topic, but also learning from peers. These are difficult things to replicate outside of a classroom. So, instead of thinking of it as forcing students to come to lecture, it’s time to create a lecture environment that is welcoming, exciting and engaging. Let’s create environments which make it so students want to come to lecture.
Amen.

I wonder what he thinks of MOOC's?


Ilene Busch-Vishniac should resign immediately as President of the University of Saskatchewan

The university of Saskatchewan fired Robert Buckingham the other day. Buckingham was Executive Director (Dean) of the School of Public Health. He objected to a policy called "TransformUS" that was designed to save the university money. It proposed to abolish the School of Public Health and merge it, and the College of Dentistry, with the College of Medicine.

He was not only fired from his administrative post, he was also fired from his tenured job as a Professor and banned from the University campus.

Buckingham and another Dean (Associate Dean Ken Sutherland of Dentistry) were warned that they should not speak out against the proposals that were being developed by the Provost and the President. He responded by publishing a letter titled "The Silence of the Deans."

According to a CBC article,
Security guards escorted Buckingham out of the building on Wednesday, the same day the Saskatoon-based university stripped him of his tenured faculty position. A termination letter reasoned that by speaking out against the school's restructuring plans, Buckingham "demonstrated egregious conduct and insubordination" and was in breach of contract.

He was also banned for life from the campus.
There are dozens of other articles in newspapers and blogs across the country that confirm these events and condemn the University of Saskatchewan.

Watch this Global TV video to get an overview of what happened and how the University of Saskatchewan Faculty Association intends to respond.

I can understand why the university might want to relieve Robert Buckingham of his job as Dean but, even then, they should tread very carefully if they are firing him only because he speaks out against the destruction of his Faculty. However, under no circumstances should the university fire a professor who is protected by the right to academic freedom—especially if the only cause for dismissal is a disagreement with the university administration.

The letter of termination has (rightly) been made public (see below). It's an extraordinary letter. I don't think this termination has a ghost of a chance in court if it should come to that. The irony is in the Provost's words, "you have damaged the reputation of the university." Any "damage" done by Robert Buckingham in speaking out against the destruction of his Faculty pales in comparison to the damage done by the Provost and the President. The stupid actions of Brett Fairbairn and Ilene Busch-Vishniac are being broadcast all over the world. It will take years to restore the reputation of the University of Saskatchewan after this.

As you can see from this CBC News report, the Saskatchewan Minister of Advanced Education is concerned about the firing. This CTV News video shows the NDP Leader of the Opposition referring to the "outrageous" actions of the university. Oops!

The first step is for the Provost and the President to reinstate Robert Buckingham to his job as professor and then the Provost and the President should resign. This should happen today, or tomorrow at the latest. If they don't resign then the governing body of the University of Saskatchewan should fire them from their administrative posts for cause. Administrative leaders of a public university cannot ignore academic freedom.



Wednesday, May 14, 2014

What did the ENCODE Consortium say in 2012?

When the ENCODE Consortium published their results in September 2012, the popular press immediately seized upon the idea that most of our genome was functional and the concept of junk DNA was debunked. The "media" in this case includes writers at prestigious journals like Science and Nature and well-known science writers in other respected publications and blogs.

In most cases, those articles contained interviews with ENCODE leaders and direct quotes about the presence of large amounts of functional DNA in the human genome.

The second wave of the ENCODE publicity campaign is trying to claim that this was all a misunderstanding. According to this revisionist view of recent history, the actual ENCODE papers never said that most of our genome had to be functional and never implied that junk DNA was dead. It was the media that misinterpreted the papers. Don't blame the scientists.

You can see an example of this version of history in the comments to How does Nature deal with the ENCODE publicity hype that it created?, where some people are arguing that the ENCODE summary paper has been misrepresented.

Tuesday, May 13, 2014

Happy Birthday to Me!

I don't normally celebrate my birthday in public but I made the mistake of putting my birth date on my Facebook page so lots of people are sending me birthday wishes.

Thank-you very much everyone. Many of your messages are quite touching.

I was born on Monday, May 13, 1946 at 6am. It was the day after Mother's Day so my mother had to wait a full year before she could celebrate her first Mother's Day. We joined her for her 67th Mother's Day a few days ago.


Monday, May 12, 2014

Monday's Molecule #240

Last week's molecule (right) [Monday's Molecule #239] was 2-carboxy-D-arabinitol 1-phosphate. It's an inhibitor of the enzyme ribulose 1,5-bisphosphate carboxylase-oxygenase, better known as Rubisco. That's the key enzyme responsible for CO2 fixation in the Calvin cycle. Plants have to inhibit Rubisco during the night when the lack of sunlight prevents production of ATP and NADPH by photosynthesis. One of the ways they inhibit the enzyme is to produce 2-carboxy-D-arabinitol 1-phosphate at night. The winner is Piotr Gąsiorowski.

This week's molecule (below) is pretty complicated. I don't expect a complete name; just concentrate on getting the correct name of the core part of the molecule on the left. In addition to identifying the molecule, you need to explain what it is used for and, specifically, the purpose of the -N3 group in the lower left corner of the molecule.


Email your answer to me at: Monday's Molecule #239. The first one with the correct answer wins. I will only post the names of winners to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Friday, May 09, 2014

How does Nature deal with the ENCODE publicity hype that it created?

Let's briefly review what happened in September 2012 when the ENCODE Consortium published their results (mostly in Nature).

Here's the abstract of the original paper published in Nature in September 2012 (Birney et al. 2012). Manolis Kellis (see below) is listed as a principle investigator and member of the steering committee.
The human genome encodes the blueprint of life, but the function of the vast majority of its nearly three billion bases is unknown. The Encyclopedia of DNA Elements (ENCODE) project has systematically mapped regions of transcription, transcription factor association, chromatin structure and histone modification. These data enabled us to assign biochemical functions for 80% of the genome, in particular outside of the well-studied protein-coding regions. Many discovered candidate regulatory elements are physically associated with one another and with expressed genes, providing new insights into the mechanisms of gene regulation. The newly identified elements also show a statistical correspondence to sequence variants linked to human disease, and can thereby guide interpretation of this variation. Overall, the project provides new insights into the organization and regulation of our genes and genome, and is an expansive resource of functional annotations for biomedical research.
Most people reading this picked up on the idea that 80% of the genome had a function.

The Case for Junk DNA: The onion test

I draw your attention to a new paper on junk DNA by my friends Alex Palazzo and Ryan Gregory (Palazzo and Gregory, 2014).

You should read this paper if you want a nice summary of the evidence for a high percentage of junk in our genome. They cover genetic load, sequence conservation, and the evidence from the genome sequence itself. There's a brief description of the nearly-neutral theory of molecular evolution and why it's relevant to the debate.1

One of the most important contributions is an explanation of the C-Value Paradox and the Onion Test. The Onion Test was originally published on Ryan's blog (The onion test) but some people won't reference blog posts so here it is in a peer-reviewed paper.
There are several key points to be understood regarding genome size diversity among eukaryotes and its relationship to the concept of junk DNA. First, genome size varies enormously among species [18], [19]: at least 7,000-fold among animals and 350-fold even within vertebrates. Second, genome size varies independently of intuitive notions of organism complexity or presumed number of protein-coding genes (Figure 1). For example, a human genome contains eight times more DNA than that of a pufferfish but is 40 times smaller than that of a lungfish. Third, organisms that have very large genomes are not few in number or outliers—for example, of the >200 salamander genomes analyzed thus far, all are between four and 35 times larger than the human genome [18]. Fourth, even closely related species with very similar biological properties and the same ploidy level can differ significantly in genome size.

These observations pose an important challenge to any claim that most eukaryotic DNA is functional at the organism level. This logic is perhaps best illustrated by invoking “the onion test” [20]. The domestic onion, Allium cepa, is a diploid plant (2n = 16) with a haploid genome size of roughly 16 billion base pairs (16 Gbp), or about five times larger than humans. Although any number of species with large genomes could be chosen for such a comparison, the onion test simply asks: if most eukaryotic DNA is functional at the organism level, be it for gene regulation, protection against mutations, maintenance of chromosome structure, or any other such role, then why does an onion require five times more of it than a human? Importantly, the comparison is not restricted to onions versus humans. It could as easily be between pufferfish and lungfish, which differ by ~350-fold, or members of the genus Allium, which have more than a 4-fold range in genome size that is not the result of polyploidy [21].

In summary, the notion that the majority of eukaryotic noncoding DNA is functional is very difficult to reconcile with the massive diversity in genome size observed among species, including among some closely related taxa. The onion test is merely a restatement of this issue, which has been well known to genome biologists for many decades [18].


1. A little birdy tells me that there's a "better" paper coming out in a few months.

Palazzo, A. and Gregory T.R. (2014) The Case for Junk DNA. PLoS Genetics (published May 8, 2014) [doi: 10.1371/journal.pgen.1004351]

Thursday, May 08, 2014

More primordial soup nonsense

I just discovered a new paper on the origin of life (Keller et al. 2014). The authors think they are looking at the first primitive biochemical pathways, which they identify as glycolysis and the pentose phosphate pathways.

Here's what they did. They took a bunch of pure sugar phosphates1 and dissolved them in water containing salts and metal ions that were likely present in the primordial oceans. They heated the solution up to 70° C and looked at the degradation products. Low and behold, the sugar phosphates degraded and sometime the products were other intermediates in the glycolytic and pentose phosphate pathway, including pyruvate and glucose.

They conclude that ...