Researchers Nigel Goldenfeld and Thomas Kuhlman noticed that “half of the human genome is made up of retrotransposons [jumping genes, “junk DNA”], but bacteria hardly have them at all” and wondered what would happen if they just inserted some:
“We thought a really simple thing to try was to just take one (retrotransposon) out of my genome and put it into the bacteria just to see what would happen,” Kuhlman said. “And it turned out to be really quite interesting.”
Their results, published in the Proceedings of the National Academy of Sciences, give more depth to the history of how advanced life may have emerged billions of years ago—and could also help determine the possibility and nature of life on other planets.
Along the way to explaining life, the researchers first encountered death—bacterial death, that is. When they put retrotransposons in bacteria, the outcome was fatal.
“As they jump around and make copies of themselves, they jump into genes that the bacteria need to survive,” Kuhlman said. “It’s incredibly lethal to them.”
When retrotransposons copy themselves within the genome, they first find a spot in the DNA and cut it open. To survive, the organism then has to repair this cut. Some bacteria, like E. coli, only have one way to perform this repair, which usually ends up removing the new retrotransposon. But advanced organisms (eukaryotes) have an additional “trick” called nonhomologous end-joining, or NHEJ, that gives them another way to repair cuts in their DNA.
Goldenfeld and Kuhlman decided to see what would happen if they gave bacteria the ability to do NHEJ, thinking that it would help them tolerate the damage to their DNA. But it just made the retrotransposons better at multiplying, causing even more damage than before.
“It just completely killed everything,” Kuhlman said. “At the time, I thought I was just doing something wrong.” More” at Phys.org
You are doing something wrong, Dr. Kuhlman. You are tinkering with an engineered system whose manual you have never read, though you may end up contributing to it. 😉
Now, what’s the story about the history of advanced life and the possibility and nature of life on other planets, as noted above?
History of advanced life:
This study suggests that group II introns, the ancestors of introns in the spliceosome and retrotransposons in eukaryotes, somehow invaded early eukaryotic cells. Then, their interactions with NHEJ created a “selection pressure” that helped lead to the emergence of the spliceosome, which helped life become advanced billions of years ago.
They “somehow invaded”? From where?
The spliceosome helped life become advanced by enabling eukaryotes to do more with their DNA. For example, even though humans have roughly the same number of genes as C. elegans, a worm, humans can do more with those genes.
No doubt, humans can do more than worms. But can we specify what the “more” is exactly? And how does it relate to “selection pressures” (the quotation marks are in the original?
About life on other planets?
“If life exists on other planets, presumably one would expect it to be microbial. Could it ever have made this transition to complex life?” Goldenfeld said. “It’s not that you’re inevitably going to get advanced life, because there are a bunch of things that have to happen.”
There are indeed “a bunch of things that have to happen.” But are we learning the right lessons from these discoveries? A vast amount of information entered the system at some point, without killing everything it touched, and we have no clue as to how that happened. Maybe we should look for patterns rather than a big fluke.
Hat tip: Philip Cunningham Follow UD News at Twitter!
See also: Humans may have only 19,000 coding genes
“Junk DNA” regulates regeneration of tissues and organs
Note: One junk DNA defender just isn’t doing politeness anymore. Hmmm. In a less Darwinian science workplace, that could become more a problem for him than for his colleagues.
Junk DNA can actually change genitalia. Junk DNA played the same role in defending Darwinian evolution as claims that Neanderthal man was a subhuman. did: The vast library of junk genes and the missing link made Darwin’s story understandable to the average person and the missing link even became part of popular culture. With Darwinism so entrenched, the fact that these beliefs are not based on fact will be difficult to root out of the culture. Darwin-only school systems are part of the problem.
Been a while since we’ve heard much about humans as the 98% or 99% chimpanzee. If the human genome is this fuzzy how would we know? And doubtless, things have gotten more complex.
At Quanta: Cells need almost all of their genes, even the “junk DNA”
“Junk” RNA helps regulate metabolism
Junk DNA defender just isn’t doing politeness any more.
Anyone remember ENCODE? Not much junk DNA? Still not much. (Paper is open access.)
Yes, Darwin’s followers did use junk DNA as an argument for their position.
Another response to Darwin’s followers’ attack on the “not-much-junk-DNA” ENCODE findings