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The Rest of the Science Community Starting to Catch Up With ID on “Junk” DNA (It Ain’t)

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The ID community, including many writers here at UD, has been predicting for years that so-called junk DNA would be  found to be functional.  The Darwinists have scoffed.  Now ID proponents are being vindicated.  My prediction:  The Darwinists will change their story to “we’ve been saying this all along.”

The Washington Post reports on the breakthrough research published in Nature.

Most of a person’s genetic risk for common diseases such as diabetes, asthma and hardening of the arteries appears to lie in the shadowy part of the human genome once disparaged as “junk DNA.”

Indeed, the vast majority of human DNA seems to be involved in maintaining individuals’ well being — a view radically at odds with what biologists have thought for the past three decades.

Those are among the key insights of a nine-year project to study the 97 percent of the human genome that’s not, strictly speaking, made up of genes.

The Encyclopedia of DNA Elements Project, nicknamed Encode, is the most comprehensive effort to make sense of the totality of the 3 billion nucleotides that are packed into our cells.

The project’s chief discovery is the identification of about 4 million sites involved in regulating gene activity. Previously, only a few thousand such sites were known. In all, at least 80 percent of the genome appears to be active at least sometime in our lives. Further research may reveal that virtually all of the DNA passed down from generation to generation has been kept for a reason.

This concept of ‘junk DNA’ is really not accurate. It is an outdated metaphor,” said Richard Myers of the HudsonAlpha Institute for Biotechnology in Alabama.

Myers is one of the leaders of the project, involving more than 400 scientists at 32 institutions.

Another Encode leader, Ewan Birney of the European Bioinformatics Institute in Britain, said: “The genome is just alive with stuff. We just really didn’t realize that beforehand.”

“What I am sure of is that this is the science for this century,” he said. “In this century, we will be working out how humans are made from this instruction manual.”

The new insights are contained in six papers published Wednesday in the journal Nature. More than 20 related papers are appearing elsewhere. . .

The new research helps explain how so few genes can create an organism as complex as a human being. The answer is that regulation — turning genes on and off at different times in different types of cells, adjusting a gene’s output and coordinating its activities with other genes — is where most of the action is. . . .

In one paper, a team led by Thomas R. Gingeras of Cold Spring Harbor Laboratory in New York reported that three-quarters of the genome’s DNA is “transcribed” into a related molecule, RNA, at some point in life. A small amount of that RNA is then “translated” into protein. Much of the rest appears to have gene-regulating activities that remain to be discovered.

In a telephone conference call with reporters, several of the researchers likened the 4 million regulatory sites to electrical switches in a hugely complex wiring diagram.

By turning switches on and off, and varying the duration of their activity, a nearly infinite number of circuits can be formed. Similarly, by activating and modulating gene function, immensely complicated events such as the development of a brain cell or a liver cell from the same starting materials is possible.

Comments
There was a discussion above about purifying selection (selection against deleterious mutations). One result from population genetics is that purifying selection isn't very effective in small populations, so mildly deleterious mutations can be fixed in the population. (Humans have a small effective population size, historically, so this applies to us to some degree. It's probably why transoposon insertions, which are probably only mildly deleterious, can be fixed in mammals) The result is that in very small isolated populations, deleterious alleles can build up quickly, increasing the mutation load severely. As it happens there is a paper in this week's PNAS on such a case. ttp://www.pnas.org/content/109/37/E2496.abstractPNG
September 13, 2012
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Chop out a nucleotide in a protein coding gene and see how it works. Do the same to an intron...wd400
September 13, 2012
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wd400: The problem is not that "every single nucleotide... is “functional” ". The problem is if introns and other non coding sites are globally functional, and what functions they do have. As Mung has very correctly mentioned, not even in protein coding genes "every single nucleotide is “functional” ". That's why we have a lot of neutral mutations. Even deletions of aminoacids can in some cases be irrelevant to the function of a protein. So, the function issue has to be judged on proper terms, and not at the single nucleotide level.gpuccio
September 13, 2012
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It can't be a strawman, because it is ENCODE's definition! And no, the degenerate nature of the genetic code is not "junk" anymore than the fact you could change most residues in a protein and not alter the functions make most positions in proteins "junk".wd400
September 12, 2012
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wd400:
But no matter the origin of introns, do really think every single nucleotide of every single intron is “functional” is a bit strange...
Straw-Man Take Threonine for example:
Threonine ... Its codons are ACU, ACA, ACC, and ACG.
As that final nucleotide in the codon "junk" because it can be any of the four and still result in the production of threonine? What 'function' does it have?Mung
September 12, 2012
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The existence of introns is certainly interesting, and a challenge to the panglossian view of the genome that some engineering-types have. But no matter the origin of introns, do really think every single nucleotide of every single intron is "functional" is a bit strange, which is one reason to discount ENCODE's 80% number.wd400
September 12, 2012
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Well, I just think introns are very interesting and remain an unsolved puzzle for biology. I just have to decide I guess how much they can be explored in a blog. Perhaps one of the first things to reflect on is the fact that introns don't exist in isolation. Would we even recognize an intron as an intron if there were not some biochemical process that excised them? But why would such a system as that arise, absent any introns in the first place? Yet another classic beef and egg problem? http://en.wikipedia.org/wiki/Intron http://en.wikipedia.org/wiki/RNA_splicingMung
September 12, 2012
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I don't really know why this is relevant, but the evidence for a single origin of introns is that fact they are limited to a single calde - Eukaryotes. Their orign is unclear - perhaps they started out as selfish elements, perhaps the splicisome etc is a relic from and RNA world that prokaryotes, with their much more efficient genomes, could remove. I'm not sure why it matters? I still think you'd have to be mad to think every nucleotide of every intron was functional. The non-adaptive origin of complexity paper is this one: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3121905/ and all models of junk DNA are non-adaptive, that's sort of the point.wd400
September 12, 2012
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wd400:
Introns evolved once...
1. What is the evidence that introns evolved? 2. Why did introns evolve at all? 3. Why did introns evolve only once?
...here are models of non-adaptive complexity (read the link in my earlier comment).
Your link doesn't work. But what I'm looking for are the models of non-adaptive junk, not models of non-adaptive complexity.Mung
September 11, 2012
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Mung, Introns evolved once, there used to be a debate about whether they were excised by prokaryotes or invented by eukaryotes, don't know where we stand on that one today. Even if they are a eukaryote invention, it's worth remembering that there are models of non-adaptive complexity (read the link in my earlier comment). Eric. OK, only about 10% of the genome is subject to purifying selection. Done?wd400
September 11, 2012
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wd400:
And no, it’s not clear why intron’s exist, but it’s worth repeating evolutionary biology doesn’t require something to have a purpose in order to exist.
Introns do not exist in all organisms. (I'm not trying to imply that you don't know that, I'm sure you do.) So did they just magically appear in numerous lineages independently? Or have they been inherited from a common ancestor? When the first intron appeared, how did it spread throughout the population? Drift? I would think that one would assume that there was some initial selective advantage. So I don't think it's at all unreasonable to think that they had some purpose, at least in the beginning. Something new appears on the scene that gives the carrier and it's descendants a reproductive advantage, by which means it is then spread through the population. Wash Rinse Repeat. Much less likely to happen if if serves no purpose.Mung
September 11, 2012
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timothya, The structured approach has been replaced by the object-oriented approach. And before the structured approach there was some other "best" way to develop software. It's probably not a good idea to just take one of them when seeking to find comparisons in biology. And as you can see, human understanding changes.Mung
September 11, 2012
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wd400:
Nah Eric, it’s like this. No one ever said every non-coding sequence was junk. Ohno, in the first papers about the idea was quite explicit about this. So finding this or that pseudo-gene now drives expression of some thing or other doesn’t disprove junk DNA.
No-one ever said anyone said that every non-coding sequence was junk. We're talking about a broader concept here. paulmc and I are discussing selection and what evidence may or may not exist about selection's action in the genome.
On the other hand, the ENCODE result includes every nucleotide of every intron in its definition of “function”. I don’t think any sane person could think every nucleotide of every intron was actually require for proper functioning of the cell (and to believe that, and that Fugu can get by fine with many times smaller introns in a real stretch), so clearly the ENCODE total is too high.
I'm not so interested in the ENCODE definition in what I am discussing, other than the fact of pervasive transcription and the implications of that. I realize you and others on the thread are focusing on the ENCODE definition. paulmc and I are talking about other aspects. However, in response to your comment I would note that you cannot assume that the ENCODE total is too high. You may end up being right that the definition is too broad and that some portions of some introns are not necessary for funcion. However, we will find more functions in the future, and we also know that some portions of DNA are important due to their placement, transcription timing 'pause' elements, and there is even multi-layered information in some elements. So it is not at all clear that 80% will be too high at the end of the day.
(BTW, this is one of those topics that exposes how the verbal tic of calling evolutionary biologists “Darwinists” is really misleading – only ultra-Darwinian biologists would think the genome was full of functions. So, the people arguing for junky genomes are actually talking about non-Darwinian theories of genome evolution)
Well, there may be better terms. Your classic ultra-Darwinist Dawkins, however, loves to proclaim how much junk DNA there is, so I'm not sure you've got your categories quite right either. :) And Darwinian evolution includes two general principles: variation plus selection. It seems the first aspect is pretty broad and picks up just about everything. Whether selection is acting or hasn't acted yet, or is only slowly acting, is of course an open question. I understand your point, however, that there may be other specific stories about how certain features came about that one could view as less Darwinian. Most of which are just variations on the overall evolutionary 'explanation' that "stuff happens."Eric Anderson
September 11, 2012
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wd400- Your entire position is a joke because you cannot explain functional DNA and you cannot explain alternative gene splicing. And again FUTURE FUNCTIONS- ie theb reason not all genes make alternative products- why so big (introns)? Because they also house software. As I said eliminate them and see what you get.Joe
September 11, 2012
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Joe. I didn't say all introns are junk, Just that encode calling every nucleotide of every one if them functional is a bit of a joke.wd400
September 11, 2012
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Loljoe, even if that is true, most genes don't make alternative products. so, why so many introns? And why so big?wd400
September 11, 2012
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wd400, Introns exist to make alternative gene splicing possible. And your position cannot explain alternative gene splicing. And we await your experiments in which you remove all introns and get a viable organism.Joe
September 11, 2012
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Mung, it's not a strawman, it's ENCODE's definition! And no, it's not clear why intron's exist, but it's worth repeating evolutionary biology doesn't require something to have a purpose in order to exist. Michael Lynch and his crew might well argue introns are non-adaptively complexwd400
September 11, 2012
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Mung: I was not proposing human software design as template for understanding the structure and functioning of biological systems. In fact, I think digital computing is a particularly poor analogy of how biological systems work. I need to say this upfront, just so Eric doesn't bark himself into a lather up the wrong tree again. I will include one partial response to Eric's comment that:
Neither you nor anyone else has the slightest clue about how biological systems could be better designed.
This would be news to generations of plant and animal breeders, developers of genetically modified organisms, developers of gene therapy solutions, stem cell researchers etc etc, all of whom by different pathways are "investigating how biological systems could be better designed" (that is, better fit to human health and requirements). I used to do it for a living, so actually I do have a clue. Enough said. My point (and probably not a particularly important one) is this. Simply asserting designedness in non-human systems on the basis of prior knowledge about how humans design things is insufficient. If, in fact, undesigned, natural processes can create complexity, then you have simply fallen prey to an illusion. We need to look at how the complexity of human designs is materialised, and pay particular attention to how human designers typically achieve desirable features - functional fitness, sustainability, upgradability, adaptability. Software design is a reasonable example of how human designers go about achieving these attributes. Any computer program (that "works") will be at least as complex as is required to deal with the processing problem at hand. The designer essentially has two canonical approaches to creating the necessary complexity. Either follow the structured design approach, in which individual functional modules are robustly designed to perform a "class" of function, and the overall program control module contains all of the complexity required to deal with the full range of potential processing inputs - deciding which functional module to call on the basis of the input case, assembling its input data, handling its output etc etc. Alternatively, the designer can embed all of the control switching capabilities into each functional module (or, as you point out, dump all control and processing functionality into one bag of code), so it can autonomously handle all possible input combinations. We would expect to see very different abstract structural characteristics of two programs written to solve a problem using the two approaches. The first would have a single, complex control structure with a minimal set of "functional" modules. The second would either have as many functional modules as there are input possibilities, or one undifferentiated processing structure with processing code, control code and variable definitions studded throughout like plums in a pudding. Now. When faced with a new input case, the designer of the first type will typically add a switch to the control module. The designer of the second type will typically modify an existing functional module to handle the new case, or even create a new module to deal with the new eventuality. Both approaches can, in principle, deliver the functional fitness attribute, but the structured design approach requires significantly less effort to deliver sustainability, upgradability and adaptability. The structure of cellular control in biological systems appears to be one of ad-hoc modification of existing processes to meet new input cases (of dazzling intricateness). It clearly exhibits the "one control system per function" model. This, in itself, is counter-evidence to the argument that there is a long-run intention for sustainability and adaptiveness behind the processes of biological systems, irrespective of whether they were designed in the first place. I happen to believe that the ad-hoc model of modifying existing systems is precisely what one would expect if the functional changes arise from random mutations in the genetic code, followed by selection under environmental pressure on the resulting phenotype. I would not expect to see a consolidated unitary control system. And it appears that reality confirms this prediction.timothya
September 10, 2012
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wd400:
On the other hand, the ENCODE result includes every nucleotide of every intron in its definition of “function”. I don’t think any sane person could think every nucleotide of every intron was actually require for proper functioning of the cell...
That's one way to set up a straw-man. But has the question "why introns" even been answered yet? To what extent are introns found in non-Eukaryotes?
The biological origins of introns are obscure. After the initial discovery of introns in protein-coding genes of the eukaryotic nucleus, there was significant debate as to whether introns in modern-day organisms were inherited from a common ancient ancestor (termed the introns-early hypothesis), or whether they appeared in genes rather recently in the evolutionary process (termed the introns-late hypothesis).
http://en.wikipedia.org/wiki/IntronMung
September 10, 2012
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Nah Eric, it's like this. No one ever said every non-coding sequence was junk. Ohno, in the first papers about the idea was quite explicit about this. So finding this or that pseudo-gene now drives expression of some thing or other doesn't disprove junk DNA. On the other hand, the ENCODE result includes every nucleotide of every intron in its definition of "function". I don't think any sane person could think every nucleotide of every intron was actually require for proper functioning of the cell (and to believe that, and that Fugu can get by fine with many times smaller introns in a real stretch), so clearly the ENCODE total is too high. (BTW, this is one of those topics that exposes how the verbal tic of calling evolutionary biologists "Darwinists" is really misleading - only ultra-Darwinian biologists would think the genome was full of functions. So, the people arguing for junky genomes are actually talking about non-Darwinian theories of genome evolution)wd400
September 10, 2012
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timothya @62, you have a lot of assumptions built into that argument that may or may not hold even for software systems, much less for an attempt to apply principles of software design to biological organisms. One could just as easily argue that what you have described are not separate modules that "ought" to be loosely coupled, but rather a single module that "ought" to be tightly coupled according to the software principle of encapsulation. Nice try though. Perhaps if you developed the argument further. I'm interested in the extent to which software design principles are present in biological systems. Biological Design Patterns anyone?Mung
September 10, 2012
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paulmc:
The challenge is to explain genomic variation broadly.
Then why are you so narrowly focused on one species of onion? :)Mung
September 10, 2012
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PaV, I think you make an astute observation. There appear to be two trends in evolutionary thought right now in regards to junk DNA. The first, which we are starting to hear occasionally, is "What junk? We never really meant it was junk." The second, championed by wd400 and paulmc here, is to dig in the heels and battle tooth and nail against every additional finding that suggests there might be more function than previously thought. The former approach will eventually become more common as more and more function (the only possible way the evidence can trend) is discovered. But it will be painful for the latter group, and I suspect we'll see plenty more defintional/rhetorical battles waged by them in the next few years before they finally throw in the towel.Eric Anderson
September 10, 2012
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timothya @62, that is one of the most absurd things I have read in a long time. Neither you nor anyone else has the slightest clue about how biological systems could be better designed. Your failed analogy (setting aside for the moment your very questionable interpretation of tightly/loosely coupled module design) is just another in the long history of pathetic attempts to say "no designer worth his salt would have done it this way." Never is a detailed analysis done; never is a better method put forward with enough detail to ever determine whether the vague assertions about 'it could have been better' are true. And lastly, as I think you mention, even if it is poorly designed, it doesn't mean it wasn't designed.Eric Anderson
September 10, 2012
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You know what I'd like to see? I'd like to see these guys who claim there is so much junk in the genome to "practice what they preach"! Wouldn't it be nice if there was a way for them to delete whatever part of the genome they think is junk in the cells of their own children? Not that I would wish that on their kids, but I'd love for there to be a way for them to put their faith into practice and then we would be able to see what they really believe. How many of these guys would have been willing to delete 98% of the genome they claimed was junk in their own cells or in their kid's cells? None, I'm sure, and that makes me question whether or not they really believe that. It's like the tightrope walker asking people if they think he could take a guy piggy back across the falls. They all say yes and then he said "Who will volunteer?" Needless to say, there were no volunteers. It's easy to claim you believe something - but when the rubber meets the road, the truth comes out.tjguy
September 10, 2012
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It is so interesting watching Darwinists make ad hoc and ex post facto pronouncements. When pseudogenes are found to have function, thus undercutting their "junk DNA" argument, they say: "Oh, what's the big deal. No one ever said that there was 'junk-DNA'." Then you have this study that shows that 80% of the genome is transcribed, and has some, minimal, "chemical" function, and they say: "See, under this definition, anything can be termed 'functional.' We all know that there's all this 'junk' in the genome. Just look at the onion." So, which way is it, boys? Have you never said there was junk, or are you saying there's all kinds of junk? As usual, your answer will be whatever you perceive is needed to prop up a failed theory. Let's hear it for Ptolemy. In the meantime, thanks for the entertainment.PaV
September 10, 2012
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In software engineering, the concept of "coupling" is used to describe the the way that software modules interact with each other in accomplishing the overall function of a computer system. This concept was pioneered by Larry Constantine and Ed Yourdon in developing the Structured Design approach (Structured Design: Fundamentals of a Discipline of Computer Program and System Design, Prentice-Hall, 1979). They describe the differences between "loosely coupled" and "tightly coupled" systems (Wikipedia provides a good summary of the ideas involved). A tightly coupled module is difficult to modify or swap out for a superior alternative without a detailed knowledge of the way that related modules do their job. Tightly coupled systems have greater interdependency between their parts, require more coordination between parts, and require greater information flow to maintain function. Tightly coupled modules may even rely on modifying the functions of related modules. Loosely coupled systems have the opposite characteristics. In systems design, "loose coupling" is to be preferred to "tight coupling". Loosely coupled systems evince good design (clear forethought about module functions, inter-module communications and the likely need to modify or enhance functionality in the future - all good teleological attributes. Tightly coupled systems, on the other hand, evince a lack of forethought, an ad-hoc approach to making things work, and a tendency to develop spaghetti code. In other words, tightly coupled systems tend to develop "organically" (designers and programmers modify the current structure in small ways to overcome the next immediate difficulty), rather than reflecting a long-term view of the function, development and maintainability of the overall system. The genetic control systems of cellular function are clearly "tightly coupled" in the sense used by Constantine and Yourdon. The expression of a protein from a gene template is mediated by a complex parallel set of genetically encoded transcription and timing controls, each of which is specific to the particular expression pathway, and has the ad-hoc characteristic of tight coupling. Hence, if design in natural biology is to be inferred by analogy to human-designed templates (we recognise design in non-human nature because it is analogous to examples of human design), then we are forced to the inference that biological systems are poorly designed. And worse yet - the more complex the cellular functions happen to be, the worse the design. Or to put it differently, if the complexity of cellular control systems demands that deliberate design is a superior explanation for their origin (compared to mutation plus natural selection, or neutral drift following by functional co-option), then we are also paradoxically forced to the conclusion that the actual deliberate design is inadequate to the long-term survival of the system. [In the interests of full disclosure, I should say that I have shamelessly plagiarised this idea from a more loosely coupled organism than I am.]timothya
September 10, 2012
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Why are none of my questions being answered!?!? I want to know what non-function DNA is! I also want to know why any scientist would label DNA as junk if it has a purpose. Can we get an illustration here also preferably applying this same kind of idea to vestigial organs?ForJah
September 9, 2012
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paulmc:
The accumulations of non-coding DNA occurs incrementally. Each addition does not waste much energy, and in small populations, selection is too weak to remove such variation.
Sorry to butt in, but that sentence jumped out at me. So what we're being told to believe is the following: 1. In small populations with long lifecycles (like humans) selection is so strong and so effective that it was able to fix in the population numerous miniscule changes over a relatively short time period of a few million years that add up to huge differences between us and chimp ancestors. 2. In small populations with long lifecycles (like humans) selection is so weak and so ineffective that it is unable to purge a massive quantity of junk that, even under the highly questionable assumption that such junk would not cause problems for cellular function, the junk at the very least: (i) utilizes the majority of the copying resources every cell division, (ii) utilizes a meaningful portion of the transcription resources on an ongoing basis, and (iii) produces nonsense RNA strands that have to be located, recognized and broken down, over and over, minute by minute, day after day, for generations. Sounds more like a convenient story than a coherent story.Eric Anderson
September 9, 2012
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