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Study: An Evolutionary "Arms Race" Shaped the Human Genome
An anonymous reader writes "An evolutionary race between rival elements within the genomes of primates drove the evolution of complex regulatory networks that orchestrate the activity of genes in every cell of our bodies, reveals new research. The race was between mobile DNA sequences known as 'retrotransposons' (jumping genes) and the genes that have evolved to control them. Scientists at the University of California Santa Cruz, identified genes in humans that make repressor proteins to shut down specific jumping genes. "We have basically the same 20,000 protein-coding genes as a frog, yet our genome is much more complicated, with more layers of gene regulation. This study helps explain how that came about," said Sofie Salama, a research associate at the UC Santa Cruz Genomics Institute who led the study."
Per topic, when pushing rapidly into a new niche, doing the new X a little better than everyone else expanding there makes you the top dog. Once a new option becomes available, it seems natural that evolutionary pressure would push towards exemplifying that niche in a short timespan. That's the whole idea behind punctuated equilibrium as a theory.
That's not to discredit the amazing work these scientists have done to deduce the mechanics of how that might have happened to early humans.
...all she was doing was imparting some of her reprocessor genes to him, thus causing blocking of the proper jumping genes, to turn him human?
Do not look into laser with remaining eye.
The title doesn't cover the interesting part of this research. The "Arms Race" it talks about isn't an arms race with genes from other groups of people. It's basically a competition within the genome itself. These retrotransposons are genes that would basically make copies of themselves all around our genomes (likely to our detriment) if there wasn't another set of genes that suppressed that activity. To use a metaphor I've seen elsewhere, the regulator genes are basically like cops that beat the street looking for criminals in the genome. The retrotransposons then evolve in response to that with ways to mask their presence from the regulator genes. This arms race happens without much in the way of any benefit for the meat body host.
Regulation of retrotransposons is relavent to retrovirus research. Also, retrotransposons are known to be disregulated in a number of neurological disorders.
Some research is dedicated to incrimental advancements in translational applications, while other efforts are directed at a more complete understanding of the whole system. Sometimes, basic research with no obvious application ends up revolutionizing how we understand disease. A couple examples include: What makes jellyfish glow? Why does feeding worms RNA silence genes? Persuit of these questions (fluorescent proteins and RNA interference) have transformed the entire field of molecular and cellular biology, which has identified drug targets and lead to new therapies.
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I know that since this is Slashdot, evolution = good, arms race = bad, so I don't know how to process the headline.
Dark Reflection
I think you're overlooking the root problem here. Science isn't geared toward to correct keywords that generate the articles that you'd like to read. From now on, we should rename "evolution" to "Kim Kardashian," "Mars" to "school shooting," and "SQL" to "Top Ten List."
absolutely -- everything is in the race. It's like suggesting more complex beings (e.g. humans) are "more evolved", when in fact they (we) were pushed out of the simpler niches by "better evolved" organisms. There's virus that uses 5 of the 6 available reading frames along a stretch of its genome... THAT is good coding (humans use 1, very rarely 2, and often none (non-protein coding)).
to err is human, to forgive is divine, to forget is... umm...
Well, before your breeding question, there's the question of how the rather non-Occamy process of sexual reproduction came into existence in the first place.
Currently, there is no functional scientific model for this.
Really guys, before putting any more effort into abiogenesis, fix this one first.
The title doesn't cover the interesting part of this research. The "Arms Race" it talks about isn't an arms race with genes from other groups of people. It's basically a competition within the genome itself.
The http://en.wikipedia.org/wiki/G... has been a standard perspective in biology for decades.
running it. Any real experiments or is this just a bunch of PhD jerk offs dry labing stuff they really don't understand?
there's the question of how the rather non-Occamy process of sexual reproduction came into existence in the first place.
Is that really much of a mystery? Gene exchange as part of reproduction has obvious advantages for speed in adaption to changing conditions. There are plenty of hermaphrodite species that show the stepping stone to specialized organs for gene exchange. Splitting into 2 sexes, each with just one set of reproductive organs, is just a cost savings, reducing the amount of otherwise unneeded organs to maintain.
Socialism: a lie told by totalitarians and believed by fools.
No! I've finally been found out for the fraud that I am.
How could I have ever have imagined that my poor spelling skills would out me as a basic science shill?
Now, the world will uncover the great conspiracy us scientists have orchestrated all this time to steal tax money for studying trivial things that will never benefit anyone.
The evolution of sexual reproduction is a major puzzle.
:)
Just going with what I read, man.
Pretty much the entire second paragraph could be included here, though the language has been "softened" from the last edit I read, which IIRC said basically "all the theories presented have major problems, so we're going to focus on why sexual reproduction can be considered advantageous and not how it happened". Well, yeah, that's tautological. Anything that happens is "explained" by a selection advantage. Unless it's genetic drift. At which point evolution becomes unfalsifiable, because if it happens suddenly, it's evolution, if it happens slowly with incremental steps, it's evolution, if it happens due to selection pressure, it's evolution, if it happens without selection pressure, it's evolution. Basically, if an act of reproduction is in there somewhere, it's evolution. Okay then... enjoy.
This is no big surprise. All the mammals have surprisingly similar DNA.
We are some batshit crazy monk...
Ooook!
Scary is what's going to happen when someone takes an ~100% accurate readout of the human genome (i.e. good enough to recreate the DNA using the readout), sits down with a computer and gene database, deletes the non-coding junk, these retrotransposons, the old virus genomes that thought they'd acheived immortality and a bunch of other stuff we think is crap, generates the genes and IVF myself an embryo with this "cleaned-up" genome.
What happens if your genome has no redundant crap (and at this point extended telometeres because why the heck not)? Forget engineering "superior" genes, let's just get rid of all the NOOPs our cells execute first and see what happens.
And what if the kid heals twice as fast as the rest of us, has a genius IQ, and lives to 150?
Technically, "evolution" is the change in statistical distribution of alleles in a genetic population over time. There's little uncertainty about that happening - every genetic change over time is absolutely evidence of evolution, in the technical sense, because there's nothing more to it than that.
Any uncertainty is about what shaped the emergence, then dominance, of certain traits among species that survived today. But of course in the case of sexual reproduction with distinct sexes, it's still a reproductive corner case only used by a small percentage of the biomass of the planet (and heck, only plants and animals do it in any form, while most of the biomass is found in the other kingdoms).
Socialism: a lie told by totalitarians and believed by fools.
Heh, seems I'm wrong about the fungi - randy little buggers.
Socialism: a lie told by totalitarians and believed by fools.
> non-coding junk
> stuff we think is crap
> redundant crap
> NOOPs
Yours is an antiquated view. What used to be called junk DNA is actually the most interesting part, because we haven't figured out what it does.
Conversely, gene exchange in stable conditions is disadvantageous since gene exchange is a source of error.
At least 10% and perhaps as much as 25% of human embryo are spontaneously aborted, often asymptomatically or with symptoms virtually identical to menstruation. Historical numbers are unavailable. Infant mortality is still very high in many parts of the world, but until recently perinatal death rates were more than 30%.
Early death of the young (as in not yet old enough to reproduce) is a phenomenon seen in virtually all sexually reproducing animals, viviparous or otherwise, and in most sexually reproducing land plants and a wide range of fungi.
There are practically-obligate asexually reproducing plants and fungi that are known to have had stable genomes for millennia; many of the largest known organisms have (almost-)clones at some distance from them.
Finally, there are organisms which reproduce both sexually and asexually depending on the stability of conditions. Most are fungi and marine plants (some are land plants), although they should not be confused with species like quaking aspen which reproduce both asexually and sexually at all times with results depending on conditions (clonal groups like Pando are more common in stable arid conditions, heterozygous groups are more common in semiarid conditions, although all groups put up both sexual parts and clonal trunks).
Essentially, there is so much diversity in sexual reproduction that there is no consistent single hypothesis for why it persists. Arguments that apply to migratory species do not necessarily apply to sessile species and vice-versa. Indeed, even in closely related species it's not especially clear that the cost of having two sexes is worthwhile. (It gets really interesting in closely related species where one species is strongly sex-selected by Wolbachia and the other is uninfested by them, since the extremely high prevalence of male-killing Wolbachia sometimes can be *advantageous* to the former population -- I think it is perfectly reasonable to hypothesize that comparable microbes are intimately linked to the arrival of colony insects).