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Thursday, February 09, 2017

NIH and UCSF ENCODE researchers are on Reddit right now!

Check out Science AMA Series: We’re Drs. Michael Keefer and James Kobie, infectious .... (Thanks to Paul Nelson for alerting me to the discussion.)

Here's part of the introduction ...
Yesterday NIH announced its latest round of ENCODE funding, which includes support for five new collaborative centers focused on using cutting edge techniques to characterize the candidate functional elements in healthy and diseased human cells. For example, when and where does an element function, and what exactly does it do.

UCSF is host to two of these five new centers, where researchers are using CRISPR gene editing, embryonic stem cells, and other new tools that let us rapidly screen hundreds of thousands of genome sequences in many different cell types at a time to learn which sequences are biologically relevant — and in what contexts they matter.

Today’s AMA brings together the leaders of NIH’s ENCODE project and the leaders of UCSF’s partner research centers.

Your hosts today are:

Nadav Ahituv, UCSF professor in the department of bioengineering and therapeutic sciences. Interested in gene regulation and how its alteration leads to morphological differences between organisms and human disease. Loves science and juggling.
Elise Feingold: Lead Program Director, Functional Genomics Program, NHGRI. I’ve been part of the ENCODE Project Management team since its start in 2003. I came up with the project’s name, ENCODE!
Dan Gilchrist, Program Director, Computational Genomics and Data Science, NHGRI. I joined the ENCODE Project Management team in 2014. Interests include mechanisms of gene regulation, using informatics to address biological questions, surf fishing.
Mike Pazin, Program Director, Functional Genomics Program, NHGRI. I’ve been part of the ENCODE Project Management team since 2011. My background is in chromatin structure and gene regulation. I love science, learning about how things work, and playing music.
Yin Shen: Assistant Professor in Neurology and Institute for Human Genetics, UCSF. I am interested in how genetics and epigenetics contribute to human health and diseases, especial for the human brain and complex neurological diseases. If I am not doing science, I like experimenting in the kitchen.

Monday, February 06, 2017

A philosopher tells us how to think clearly about evolutionary causes ... avoid adaptationism

I think philosophy has lost its way. The discipline gives credence to religious philosophers who write about god(s) and to other philosophers who reject determinism and think the mind-body problem is still an open question. Philosophers still debate the validity of the ontological argument. Philosophers of science have not even settled the question of what is science, let alone come up with a valid answer of how to do it. There are few other disciplines that are still respected after several hundred years of trying, and failing, to answer the most fundamental questions in their field. Many academic philosophy department are hotbeds of political correctness and just plain politics.

Friday, February 03, 2017

Ricky Gervais explains atheism

Watch Ricky Gervais explain atheism to Stephen Colbert. I like his explanation of the difference between science and religion. In fact, I like it so much I'm going to embellish it a bit and present it here ...

Imagine what would happen after a giant meteor strike that wipes out everyone except for a small native tribe in the Andes that had no contact with other people before the apocalypse. All books and all knowledge will be destroyed.

Ten thousand years later there will be science books and they'll be pretty much the same as the ones we have now because people will simply rediscover the basic truths of nature. There might be religious books but they won't be anything like the holy books we have now because the people will have invented entirely new gods. That's the difference between science and religion.



Why is life the way it is?

Nick Lane is very good at explaining complex biology and biochemistry. He is the winner of the Royal Society's Michael Faraday Prize for 2016. Here's his lecture. It's worth watching if you want to understand the latest informed (naturalistic) speculations on the origin of life.




Trying to educate a creationist (Otangelo Grasso)

Otangelo Grasso is a creationist who's convinced he can learn to understand biochemistry by reading what's on the internet and copy-pasting it into his website. He then takes that limited knowledge and concludes that evolution is impossible. He often poses "gotcha" questions based on his flawed understanding.

His behavior isn't very different from most other creationists who suffer from Dunning-Kruger Disease but he happens to be someone who I thought could be educated.

I was wrong.

Over the years I've tried to correct a number of errors he's made so we could have an intelligent discussion about evolution. You can't have such a discussion if one side ignores facts and refuses to learn. Here's an example of a previous attempt: Fun and games with Otangelo Grasso about photosynthesis. Here's a post from yesterday showing that I wasted my time: Otangelo Grasso on photosynthesi.

Thursday, February 02, 2017

Discovery Institute publishes another anti-evolution book

It's not Saturday morning but you can enjoy this cartoon anyway.


Tom Bethell ... writes like a dream.
                      —Fred Barnes


Wednesday, February 01, 2017

Scientists confused about photosynthesis - press release makes it worse

Photosynthesis is the series of reactions that capture light energy and use it to make ATP and sometimes reducing equivalents (e.g NADPH). There are many different versions of photosynthesis. One of the simplest is found in purple bacteria where the process results in formation of a proton gradient that's used to drive ATP synthesis.

Sunday, January 29, 2017

The evolution of the citric acid cycle

I just realized that I don't have a post devoted to the evolution of the citric acid cycle. This need to be remedied since I often talk about it. It's a good example of how an apparently irreducibly complex pathway can arise by evolution. It's also a good example to get students to think outside of the box. Undergraduate biochemistry courses usually concentrate on human physiology and too often students transfer that bias to all other species. They assume that what happens in humans is what happens in plants, fungi, protozoa, and bacteria.1

Here's what the standard citric acid cycle looks like (Moran et al., 2011 p. 393).

Wednesday, January 25, 2017

Once again, the IDiots don't understand evolution

This is so frustrating. I've been debating creationists for almost 30 years. My colleagues and I have tried time and time again over those three decades to educate them about real evolutionary theory. We've also tried to teach them about the difference between evolution and the history of life. In order to explain the history of life on Earth you need to account for mass extinctions and other chance events that have nothing to do with evolution. They refuse to listen.

The latest evidence is a recent post by David Klinghoffer [Theory of Evolution? Call It a "Narrative" Instead]. He says,
The theory of evolution by natural selection operating on random mutations, as a sweeping explanation for life and how it got there, is a "narrative." It presents a very smooth story, persuasive to most scientists. The facts may all be true, but the conclusion: BS.
No knowledgeable scientist thinks that natural selection is the only mechanism of evolution so no knowledgeable scientist thinks that mutation + selection explains the history of life. That's just BS. Not only are scientists aware of what modern evolutionary theory actually says but they're also aware of other factors that determined the history of life.

Now you know why we call them IDiots. What is it that makes them so resistant to learning about the ideas they so adamantly oppose? They can still oppose correct ideas if they want. Isn't that better than fighting strawmen?


Monday, January 23, 2017

Why does the human population carry an allele that increases the risk of Alzheimer's?

The human apolipoprotein E gene (ApoE) has several alleles segregating in the human population. One of them, E4, is associated with increased risk of Alzheimer's. Ed Yong, writing for The Atlantic, asks "Why Do Humans Still Have a Gene That Increases the Risk of Alzheimer's?

I can think of several answers off the top of my head. The most important one is that Alzheimer's has very little effect on your ability to have children. The disease may not even have developed in most of our ancestors who tended to die younger. In order to be subject to negative selection the allele has to affect adults before they reproduce.

The second reason is that the slight deleterious effect, if there is one from an evolution perspective, may not have been significant enough in small populations. I know, and I hope my students know, that neutral and deleterious alleles can reach significant frequency in a population by chance. The general public doesn't know this.

Check out Ed Yong's article to see his explanation.
“It doesn’t make sense,” says Ben Trumble, from Arizona State University. “You’d have thought that natural selection would have weeded out ApoE4 a long time ago. The fact that we have it at all is a little bizarre.”


Thursday, January 19, 2017

The pervasive transcription controversy: 2002

I'm working on a chapter about pervasive transcription and how it relates to the junk DNA debate. I found a short review in Nature from 2002 so I decided to see how much progress we've made in the past 15 years.

Most of our genome is transcribed at some time or another in some tissue. That's a fact we've known about since the late 1960s (King and Jukes, 1969). We didn't know it back then, but it turns out that a lot of that transcription is introns. In fact, the observation of abundant transcription led to the discovery of introns. We have about 20,000 protein-coding genes and the average gene is 37.2 kb in length. Thus, the total amount of the genome devoted to these genes is about 23%. That's the amount that's transcribed to produce primary transcripts and mRNA. There are about 5000 noncoding genes that contribute another 2% so genes occupy about 25% of our genome.

Wednesday, January 18, 2017

Pyruvate dehydrogenase astonishes Ann Gauger

Ann Gauger was reading a cell paper the other day [Digging Deep in Biology: "Things Get Even More Complicated When You Look Closer"]. The subject was the localization of citric acid cycle enzymes and pyruvate dehydrogenase (PDH). She did a little digging and this is what astonished her ...

... so I looked up pyruvate dehydrogenase and found to my astonishment that it is not one enzyme but an enormous complex of three different enzymatic activities clustered together on a cube-shaped core of 24 units, or alternatively a dodecahedral core of 60 units. The enzymes work together to turn pyruvate into acetyl CoA in a three-step process, handing off to each other as the reaction proceeds.

Sunday, January 15, 2017

Why are most biologists adaptationists?

I enjoyed listening to Michael Lynch's talk on Friday. Much of what he said has been covered in Sandwalk over the past few years. His main point was that nothing in biology makes sense except in the light of population genetics. He laments the fact that most biologists, and even most evolutionary biologists, don't have a firm grasp of population genetics and the importance of random genetic drift.

I asked him why he thought this was true. He said he didn't know why. I think he was being polite. If you read his book, "The Origins of Genome Architecture," you'll see that he attributes this phenomeon to ignorance of modern evolutionary theory.

Saturday, January 14, 2017

The dynamic duo tell us about five problems with evolution

Here's a link to a remarkable radio interview with Stephen Meyer and Doug Axe. The subject is the Royal Society meeting last November on New trends in evolutionary biology: biological, philosophical and social science perspectives. The theme is not Intelligent Design Creationism, instead it's all about so-called problems with evolutionary theory. That's really what ID is all about in spite of what the IDiots may claim. [see A Royal Pain: Stephen Meyer and Douglas Axe on Five Problems for Evolution.]

Here are the five problems according to IDiots.
  1. Fossil record (Cambrian explosion)
  2. The origin of information (no known natural source of information)
  3. The necessity of early mutations (you can't mutate regulatory genes that act early in development because all mutations in those genes are lethal)
  4. Epigenetic information (you can't evolve new body plans by mutating DNA because development is controlled by non-DNA epigenetic information)
  5. The universal design intuition that we all have (everybody thinks that people are created by a god-like designer, even atheists, so it must be true)