The Mystery of Googolplex: Trillion-DNA Strands in California Mud

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Discussion Overview

The discussion revolves around the discovery of large extracellular DNA strands in California mud, potentially linked to methanogenic bacteria and their implications for evolution and genetic integration in organisms. Participants explore the concept of DNA incorporation into genomes, lateral gene transfer, and the historical context of viral DNA in human genetics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants note that the DNA strands may be incorporated into an organism's genome, potentially aiding in evolution and adaptation.
  • There is a suggestion that culture-based experiments could further investigate the properties of these DNA strands.
  • One participant raises the idea of lateral gene transfer, traditionally associated with microbes, and questions its relevance to eukaryotic cells.
  • Another participant mentions rare cases of DNA integration among metazoans, citing bdellid rotifers as an example.
  • Discussion includes the fact that humans have about 8% of their DNA derived from retroviruses, which integrate viral DNA into the human genome.
  • Participants speculate on the potential outcomes when new genes integrate into a host's genome, including possible evolutionary adaptations.
  • There is a cautionary note that many ancient viral sequences in human DNA may be inactive, leading to a perception that nothing happens with these integrations.
  • One participant references the complexity of viral taxonomy compared to other life forms, highlighting the concept of "quasispecies."

Areas of Agreement / Disagreement

Participants express a range of views on the implications of DNA integration and lateral gene transfer, with no clear consensus on the outcomes or significance of these processes. The discussion remains unresolved regarding the broader implications of these findings.

Contextual Notes

Participants acknowledge the complexity of genetic integration and the historical context of viral DNA in human genomes, but the discussion does not resolve the uncertainties surrounding these topics.

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TL;DR
Extracellular huge DNA strands found in anoxic soils. The strands were named 'borgs' because the kid of the researcher suggested it - too much Star Trek I guess.
https://www.sciencemag.org/news/202...equences-known-borgs-recovered-california-mud

These are extracellular very large DNA strands that have some methanogenic DNA sequences. The researchers feel that these bacteria may be the source of borgs. Since growing methanogens in the lab is difficult, the researchers have rely on searching through incredible numbers of DNA strands found in samples of mud. The article mentions sorting through literally trillions of extracellular DNA strands in the samples.

-- posted because, in part, names for new "things" sometimes are inspired by children. Example from Mathworld:

Googolplex is a large number equal to. (i.e., 1 with a googol number of 0s written after it). The term was coined in 1938 after 9-year-old Milton Sirotta, nephew of Edward Kasner, coined the term "googol" and Kasner extended it to this larger number (Kasner 1989, pp. 20-27; Bialik 2004).

Googolplex -- from Wolfram MathWorld​

https://mathworld.wolfram.com › Googolplex
 
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If I read it correctly, another interesting point is that it is possible for these DNA strands to be incorporated into an organism's genome perhaps helping them to evolve and adapt to new environments. Should we let our kids play in the dirt?
 
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How bizarre. Hopefully, they can get some culture-based experiments done.
 
gleem said:
If I read it correctly, another interesting point is that it is possible for these DNA strands to be incorporated into an organism's genome perhaps helping them to evolve and adapt to new environments. Should we let our kids play in the dirt?
With Eukaryotic cells?

Lateral transfer has been known about for a while but I always associated it with microbes plasmids etc
 
There are rare cases among metazoans (animals).
Bdellid rotifers provide a well documented, long term example.
 
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FWIW humans have about 8% of DNA is from other "things", notably retroviruses, which embed viral DNA into our DNA. Termed "DNA integration"

Example:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC509317/ ::
[synopsis]
[snip]
...
Retroviruses use viral enzymes to copy their own genome, which is stored in an RNA transcript, into DNA. Now recognizable by the host's genome, the virus can integrate into one of the host's chromosomes. In this study, Mitchell et al. studied vectors derived from the human immunodeficiency virus (HIV), avian sarcoma-leukosis virus (ASLV), and murine leukemia virus (MLV). Introducing the viral vectors into human cells, the authors analyzed the gene expression profiles of the cells to determine where vectors integrate into human chromosomes and which, if any, genes they activate. ...
[/snip]
[/synopsis]
 
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What happens when one of these new genes strikes a chord with the host's genome?
 
It would have to integrated into the new genome.
Then it would probably evolve to better work with that specific genome it ended up in (interact better with the other parts of the genome).
May eventually (over long periods of time) evolve new functions
 
Often times nothing happens. This perception is because of the DNA having been there for really long periods of time. The genes in the DNA appear not to be expressed. Note the weasel words...

They are usually called 'Ancient virus'. They are virus genome sequences that have been "dragged along" in our genome going as far back as 40 million years. Most seem to be inactive. The sequences came from three genera: Bornavirus, Ebolavirus, and Margurgvirus. Note that virus taxonomy is really weird compared to plant and animal taxonomy. There no species in viral taxonomy, there are what are termed "quasispecies" of virus.

Ancient DNA from these viruses make up about 8% of human DNA.
Source:
DOI: 10.1371/journal.ppat.1001030
Unexpected inheritance: multiple integrations of ancient bornavirus and ebolavirus/marburgvirus sequences in vertebrate genomes
Vladimir A Belyi 1 , Arnold J Levine, Anna Marie Skalka

For a better answer to @gleem
-> A more student friendly article about 'the non-human living in you':
https://www.cshl.edu/the-non-human-living-inside-of-you/