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Could “dark DNA” change the way we think about evolution?

Denyse O'Leary
August 26, 2017
Genetics, Intelligent Design
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From Adam Hargreaves at The Conversation:

DNA sequencing technology is helping scientists unravel questions that humans have been asking about animals for centuries. By mapping out animal genomes, we now have a better idea of how the giraffe got its huge neck and why snakes are so long. Genome sequencing allows us to compare and contrast the DNA of different animals and work out how they evolved in their own unique ways.

But in some cases we’re faced with a mystery. Some animal genomes seem to be missing certain genes, ones that appear in other similar species and must be present to keep the animals alive. These apparently missing genes have been dubbed “dark DNA”. And its existence could change the way we think about evolution.

My colleagues and I first encountered this phenomenon when sequencing the genome of the sand rat (Psammomys obesus), a species of gerbil that lives in deserts. In particular we wanted to study the gerbil’s genes related to the production of insulin, to understand why this animal is particularly susceptible to type 2 diabetes.

But when we looked for a gene called Pdx1 that controls the secretion of insulin, we found it was missing, as were 87 other genes surrounding it. Some of these missing genes, including Pdx1, are essential and without them an animal cannot survive. So where are they? More.

One hopes that dark DNA will not meet the same fate as dark matter and dark energy: = all theory, no capture. Of course, in this case, the DNA must in principle exist*—unless development can take place in the absence of DNA, which is maybe a stretch.

*By contrast, if physicists are mistaken about certain aspects of our universe, dark matter and/or dark energy may not in fact exist. Think ether and phlogiston to get the picture.

See also: Researcher: DNA folding in Archaea very similar to complex cells. “It just blows my mind.”

Comments
> Has evolutionary theory ever failed in one of its ‘predictions’? Absolutely. Over a century of scientific ignorance imposed by Darwinian dogma. Now we hear that Darwin (and his cult of followers) were wrong.
It turns out that Darwin and a century of biologists following him were wrong in one key respect: evolution does not always plod along at a snails pace. - Improbable Destinies
Only one, mind you. ;) Mung
Mung: Has evolutionary theory ever failed in one of its 'predictions'? ;) PaV
All the missing genes in the lineages that evolutionists predict evolved should be found in genomes of related organisms but are not will be now call "Dark DNA" meaning we have no idea what happened to them but evolution must be true...so you go figure... J-Mac
Could “dark DNA” change the way we think about evolution? Nope. At least not in my case. The only thing that could change the way I think about evolution is that someone explains it to me. Obviously, after they explain it to professor Tour first. :) PS. I like to post comment @7. Cool! Dionisio
The increasing role of RNA in evolutionary theory and life origins is not new and faces different problems; i.e the plausible source of energy... J-Mac
Why would any evolutionist even believe the central dogma? If RNA preceded DNA why can't we have RNA -> RNA -> Protein or even just RNA -> Protein? I predict that we'll find an increasing role for RNA and that evolutionary theory will have predicted it all along. :) Mung
A telling comment from the article:
All the genes within this mutation hotspot now have very GC-rich DNA, and have mutated to such a degree that they are hard to detect using standard methods. Excessive mutation will often stop a gene from working, yet somehow the sand rat’s genes manage to still fulfil their roles despite radical change to the DNA sequence. This is a very difficult task for genes. ?It’s like winning Countdown using only vowels. This kind of dark DNA has previously been found in birds. Scientists have found that 274 genes are “missing” from currently sequenced bird genomes. These include the gene for leptin (a hormone that regulates energy balance), which scientists have been unable to find for many years. Once again, these genes have a very high GC content and their products are found in the birds’ body tissues, even though the genes appear to be missing from the genome sequences.
Looks like they're saying that they know the gene products are there, but that current genome analysis can't 'find them' because of the high GC regions---or, at least, this is what they're guessing is happening. PaV
"Dark DNA" is another way of stating Behe's First Law of Adaptation: you eliminate stuff. As the Second Law of Thermodynamics tells us that 'entropy is always increasing,' Behe's First Law tells us that 'information is always decreasing.' I say: Let the fun begin!!!! Ten years ago (or more), I wrote here at UD that genome analysis would either prove Darwinism correct and ID wrong; or, the other way around. Darwinism is about to collapse. As I say: Let the fun begin!!! BTW: I remember trapping 'kangaroo mice' in the upper desert of Mojave in November as part of a field class in biology. I've never been so unprepared for, and bitten by, the cold. A mile up. Boy was it cold. They also have a mechanism for preserving water. Their "loop of Henle" was very elongated (IIRC). PaV
Mung, If Darwinists don't believe this nonsense, they would have to turn to reality they cannot and don't want to accept no matter what...This is where the wisdom is hidden and the incoherence, often deliberate, exposed... J-Mac
By mapping out animal genomes, we now have a better idea of how the giraffe got its huge neck and why snakes are so long. Genome sequencing allows us to compare and contrast the DNA of different animals and work out how they evolved in their own unique ways.
Does anyone actually believe this? Mung

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