Hte* mysterious DNA

[Cain]

*Hte is the new Teh

http://www.livescience.com/health/081009-mystery-dna.html

The researchers call these mystery snippets "ultraconserved regions," and found that they are about 300 times less likely than other regions of the genome to be lost during the course of mammalian evolution. Bejerano and his graduate student Cory McLean detailed the finding in the journal Genome Research.

The fact that these segments haven't been weeded out by natural selection implies that they serve an important function in mammals. Yet mice in the lab bred to lack four of these DNA strands appear healthy and don't seem to be missing any vital genes.

Wondering if the odd results were simply some fault of the lab experiment, and perhaps the mice really weren't as well off as they seemed, the researchers investigated whether any other mammals were also blithely living without these regions.

Amazingly, they found that was not the case. The researchers compared ultraconserved sequences of at least 100 base pairs shared by humans, macaques and dogs with the DNA of rats and mice. They found that less than one-tenth of 1 percent of the segments shared among the primates and dogs were missing in the rodents. In contrast, about 25 percent of regular, not ultraconserved, regions in the first group were absent in the mice and rats.

"What's striking about this research is that [the regions] really are almost never lost," Bejerano told LiveScience. "You're asking if a species can live without these regions, and the resounding answer from our paper is that they seem to have an effect that is strong enough that evolution would weed [individuals without the regions] out of an evolving population."

You can read the rest of the article at the link.  According to the Techoccult site, this finding fits in quite well with the theories of Dr. Andras J. Pellionisz, who believes that "genes aren't a sequential list of instructions but rather a fractal and iterative template for organic growth" and can be read at http://www.fractogene.com/

Technoccult also suggests that Pellionisz's theories match up with the previously mentioned Chris King in interesting ways.

[Kai]

This is extremely interesting. I've never heard of ultra conserved regions before.

That these regions would be conserved and yet have no immediate biological function can lead a person to think there is something about them that we do not yet know about.

On the other hand, ascribing value to components or structures just because they exist can lead to panglossia. Its like my interest in the caddisfly larval trochantin. Its so enlarged compared to other insects, sometimes to the point where it is the size of the head, yet that may serve no function at all.

Looking at that fractogenes site, I'm reminded how much emergence is important in biology, where collective actions of parts, whether it be genes, cells, or the nervous system, leads to something greater than the parts (an organism, organ systems, consciousness). The animation there was interesting in that sense, showing an emergent structure from something very simple just generated through 4 iterations. Consider that many of these sequences have many many repeats. So, we see fractal structure in the emergent macrostructure of organisms, why not see it occuring in DNA as well? Fractals are proven methods of stability in nature and they are very simple to construct because they are simply repeats of a single basic structure.

This also makes me think of Barbara Mclintock, a corn geneticist who showed that genes can move around the genome ("jumping genes").

Ah, now I'm rambling. Sorry.

[Cain]

I have honestly no clue when it comes to the fractals or anything, so I couldn't even tell you if it was a plausible theory or not.  I have some stuff on it, but, well...I think everyone here knows about my reading list by now.  Still, regardless of status, both the fractal stuff and the ultra conserved regions are interesting, and that is more than enough for me for now.

[Kai]

I have honestly no clue when it comes to the fractals or anything, so I couldn't even tell you if it was a plausible theory or not.  I have some stuff on it, but, well...I think everyone here knows about my reading list by now.  Still, regardless of status, both the fractal stuff and the ultra conserved regions are interesting, and that is more than enough for me for now.

It would make sense, I mean, if Hox genes control the overall superstructure, then fractalgenes could control the underlying fractal structure of many body systems. If there was a gene for every minutia in an organism when it comes to what goes where, the genome would contain a whole lot more hox genes than it does. If fractal genes control things like capillary branching, the networking of nerve cells, and other super structures that seem to work within a fractal network (like lymph circulation, or tracheoles in the lungs) then that would be a much simpler system for producing those structures. Any communication and transportation system in organisms has some sort of fractal structure at some point. Fractal genes (just throwing it out there) could be the way that organisms were able to make the jump from more simple multicellular to the diversity of life we see on this planet today, because if you think about it, the difference between protozoa and simple algae is the lack of a transport/communication system on a large scale.

Interesting.

[Requia ☣]

Ok, the fractal nature of complex organisms thing isn't really new to me, but what exactly is fractal DNA?  Is this just the sequences that give thigns a fractal nature, or some specific idea about how the DNA itself works?

[Kai]

Ok, the fractal nature of complex organisms thing isn't really new to me, but what exactly is fractal DNA?  Is this just the sequences that give thigns a fractal nature, or some specific idea about how the DNA itself works?

Its repeated DNA sequences that lead to some sort of fractal nature in structure due to each consequential iteration. I think.