10 ms·

A DNA ‘parasite’ may have fragmented our genes

156 points by theafh 4y ago

dboreham 4y ago
Sometimes little frustrating that people writing articles in this field seem to have no exposure to computer science. This is the gene equivalent of a filesystem: the DNA fragments are like disk blocks. The interposing sections are file metadata. The shearing mechanism is the filesystem reconstructing a stream from the lower layer blocks. There's probably some redundancy and error correction in there too. It needs a filesystem for the same reason they were invented for computers: to provide an impedance match between the upper layer semantics (a stream of pairs describing a protein) and the lower layer storage (blocks). Using block structured storage is more flexible in terms of being able to insert in the middle of a file, etc etc.
- monocasa 4y ago
  I don't think that's a great comparison. Exons already have sequences that mark 'block' boundaries; amino acids are encoded in triplets of base pairs, but sort of like you see in 8b/10b encoding, there are sequences that are valid but only used for control purposes and don't correspond to amino acids.
- rco8786 4y ago
  That's a weird thing to get frustrated about...that someone in a completely unrelated field didn't have the experience or courtesy to explain something using analogous terms to the thing you happen to be an expert on.
  - aeonik 4y ago
    I don't think they are unrelated fields. Computer science is the study of computation. DNA, to me, is clearly a quaternary computation system. I think there is a lot for both fields to learn by studying knowledge from each. Bioinformatics seems to be on that track.
    - anonymouskimmer 4y ago
      We've got DNA which is basically a storage system. RNA can be catalytically active on its own. Typically RNA and proteins, or complexes of such, act on DNA in various manners. Maybe you're right in some way, but also consider whether using the nomenclature and ideas used to described processes of DNA repair, transcription, and translation in biology to describe electronic computation works well. If it does work well, then maybe the reverse would also work well. If it leaves much to be desired, then consider the possibility that computer science ideas may be too specific to electronic or mechanical computation.
    - rco8786 4y ago
      Cool so what's the last thing you described to your team using terms from DNA research?
      - spullara 4y ago
        genetic optimization algorithms?
  - vkou 4y ago
    Doubly so, when the two domains don't actually map cleanly to eachother. DNA is not a computer program, or a file, or storage. There's no real distinction between data, metadata, and 'code' in it, either in structure, or in practice.
- afavour 4y ago
  I don’t want to sound dense here but why is it frustrating that people who write about genetics aren’t familiar with computer science?
  - agumonkey 4y ago
    I can have similar thoughts at times. People in one field have their own lens to see the world and might miss some structures / patterns that exist in other domains. I felt it was a bit pompous to read a few medical books about the cardiovascular system, a lot of ceremony to describe an organic pump. You'd have to read mathematically inclined papers to start reading about equations and principles rather than latin nomenclature. Which I think is what the grandparent was wishing for. ps: I absolutely do not put computing above other fields though. I just wish for some pragmatic polymathism sometimes.
  - elchief 4y ago
    I suppose because they spent 6-8 years of their early adult lives focusing exclusively on biology and not computer science
- sorokod 4y ago
  It needs a filesystem for the same reason they were invented for computer Why would that be true? It is a cool analogy but implying that it is the reason requires much more.
  - renewiltord 4y ago
    Without taking a stance on whether it's right, I believe that is explained right after your quote cut-off.
    - sorokod 4y ago
      That the biology of processing DNA is subject to similar constraints and solutions computer have dealing with disk storage is remarkable. Justification is needed.
      - bronson 4y ago
        At a coarse level, both are affected by information theory, so some parts may look vaguely similar. Sure, it’s plausible you’d find related solutions, especially if you really squint. But it’s like trying to explain how atoms work using a solar system analogy. It might help with the really easy stuff, maybe? (orbitals) But sticking with it makes going any deeper pretty confusing.
- kleer001 4y ago
  https://en.wikipedia.org/wiki/Curse_of_knowledge https://en.wikipedia.org/wiki/Curse_of_knowledge
- otherme123 4y ago
  There are organisms with almost no introns, no redundancy, no CRC, no "metadata" and even overlapping genes to save space, like Giardia genome ( https://www.science.org/doi/10.1126/science.1143837 https://www.science.org/doi/10.1126/science.1143837 ). Lots of virus have all their genes encoded without introns, and almost all the genome is encoding something. I've never seen DNA as close to a filesystem, and our current best bet on introns functions are they are used to create alternative splicing products from the same DNA chunk. I cannot identify this function in a filesystem, where you can obtain two or three different valid files from the same data just by skipping some blocks.
  - pazimzadeh 4y ago
    What is CRC? Metadata is everywhere... histone modifications, glycosylation, etc..
    - anonymouskimmer 4y ago
      Cyclic redundancy check? And there is almost always basic redundancy in non-viral organisms (and many viruses) in that DNA is typically double-stranded, and most organisms have repair machinery that can rewrite across single-strand lesions using the opposite strand (this fails at double-strand lesions).
  - GauntletWizard 4y ago
    I can - It's called COW Snapshotting. Modern filesystems like ZFS and BTRFS don't ever overwrite parts of the file that change. They abstract it away by keeping an ordered list of blocks. Snapshots are simply copies of the old list. The analogy doesn't go very far, however.
    - bronson 4y ago
      COW just dedupes, it doesn’t produce alternatives. Maybe a filesystem that figures out how your spreadsheet can be stored partway into an executable, with no loss to either? Yeah, this analogy doesn’t seem real helpful.
    - 4y ago
- deleted 4y ago
  [deleted]
- inciampati 4y ago
  I don't like appeals to authority, but as a computational biologist, I am both a computer scientist and a biological scientist. So understand that I'm responding to you as exactly the kind of person you think should be drawing the kinds of links that you're suggesting. I'm sorry, but this is just not a reasonable analogy. DNA sequences are not like computer files. The reason that they're distinct modules in these sequences is due to the need for evolution to be feasible. And also for the basic reason that the sequences are linear and so modules tend to appear in these linear sequences. But there also tremendous nonlinearities as well. Things at very long distances can be importantly related to each other. The introns are not metadata. There are regions that can be removed selectively and in combinations to cause diversity in the produced proteins. That diversity is advantageous because it allows a single DNA sequence to present many different proteins that are typically related, but can be very different structurally. This splicing capability has evolved apparently from entities that can be seen as endogenous viruses or DNA parasites that have the ability to insert and splice themselves out of DNA and RNA sequences. In many confusing words, that's what the article or pointing at is talking about. The introns do provide a kind of redundancy, but only in the sense that there are areas that can be modified with minimal effect on cellular function, at least relative to modification of the exons, which directly correspond in a one to one way with proteins. There is error correction. It's called homologous chromosomes. Everyone talks about there being one genome, but in most complex forms of life, you have more than one copy per cell, usually two, and often more. These multiple copies, in addition to allowing for recombination and sexual reproduction, provide templates on which errors which arise during life can be corrected. However, there are no error correcting codes. If you'd like to learn more about the actual details of these systems, I strongly suggest an undergraduate molecular biology textbook. The best one in existence is called the Molecular Biology of the Cell. There are indeed many similarities between computing systems and biological systems, but the analogies you are making don't appear to be clear. Read a book like this, deeply and slowly, and it might change your life. At very least, it'll mean that the world you live in is much less mysterious and much more exciting.
  - pazimzadeh 4y ago
    Aren't introns like pieces of code that have been commented out? But they also change the 3D conformation of the DNA itself, which changes access by transcription factors, etc.
- gus_massa 4y ago
  You look interested in the subject, but I recommend to read a few biology books about it. There are many weird low level features of DNA that are not so cover in popular discussions [1] [2]. But I don't remember any that is similar to a filesystem as you propose. Take a look, you will be gladly surprised. [1] One of my favorites is that the bases of ADN are translated in groups of 3 to amino acids, so the code reads like AAABBBCCCDDDEEEFFF It's very unusual, but there are some virus that read the same part in two ways, with different offset, so the same part is interpreted as -JJJKKKLLLMMMNNN-- I don't remember if they use the other offset too --PPPQQQRRRSSSTTT- [2] Another, not so interesting but relevant. Eukaryote has linear DNA, so they have some special repetition in the extremes. The idea is that the extremes are difficult to copy by the usual enzyme that copy the main part that has assorted code. But the extremes have a special easy pattern, so the cell can use some specialized enzyme to make them longer.
- bashinator 4y ago
  Nope, at best the filesystem is an analogy. Just like the stretchy rubber mat isn't a perfect description of spacetime.
- anonymouskimmer 4y ago
  > It needs a filesystem for the same reason they were invented for computers: to provide an impedance match between the upper layer semantics (a stream of pairs describing a protein) and the lower layer storage (blocks). Using block structured storage is more flexible in terms of being able to insert in the middle of a file, etc etc. As a non-CS person I find this explanation opaque.
- AllegedAlec 4y ago
  https://xkcd.com/793/ https://xkcd.com/793/
fnordpiglet 4y ago
I for one welcome our new introner overlords.
MagicMoonlight 4y ago
That’s sneaky. Ironically more like a computer virus than the classical viruses. Taking over the host and modifying its boot partition so that it permanently gets produced by the system.
- anonymouskimmer 4y ago
  There's basically no such thing as a boot partition. The machine of life has been turned on since the beginning. At this point, with all of the changes since the beginning, it's not obvious that there's a "boot partition" left that could reactivate life should it shut off. All cellular progeny is made with already functional and switched on proteins and RNA. The best you get to shutting off (without permanent cell death) would be the computer equivalent of hibernation. All the proteins and RNA are still there just waiting for the signal to activate again.
  - jamiek88 4y ago
    Crazy to think we are all here because of that first multi cellular organism splitting over and over and over. Life doesn’t reboot as you say, it is split off from other organisms whether seed, sperm, rhizome or any other method it’s just cells dividing and spitting off other cells. Mind boggling to me.
    - anonymouskimmer 4y ago
      Yeah. I've known this for years but it really struck me when I typed it out here.
    - __MatrixMan__ 4y ago
      The idea that we all branched from a single ancestral organism has never sat well with me. Whatever started that process, however improbable... Well the universe allowed it to happen. Why expect that the universe wouldn't subsequently continue to let it happen, again and again?
      - 4y ago
masswerk 4y ago
"spliceosomes" – I'm somewhat disappointed. (Not really the true greco-roman spirit.)
fjfaase 4y ago
Bert Hubert has an interesting idea about the reasons for interons. He explains this in his talk 'DNA: More Greatest Hits (SHA2017)' The interesting bit, with some introduction, starts at: https://youtu.be/rCdhsN--Mdo?t=1440 https://youtu.be/rCdhsN--Mdo?t=1440 This is a follow-up talk to his talk: 'DNA: The Code of Life' https://www.youtube.com/watch?v=EcGM_cNzQmE https://www.youtube.com/watch?v=EcGM_cNzQmE
neoyagami 4y ago
oh. a "descolada"
- elevaet 4y ago
  Care to explain what you mean here?
deleted 4y ago
[deleted]
koeng 4y ago
My favorite quote I saw or heard somewhere on the rogue genetic elements in us all: “We are but a raft of genes in an ocean of retrotransposons” A little hyperbolic, but dang there are a lot
stuckinhell 4y ago
Biology is truly fascinating, the ultimate hardware/software combo of proteins/genes. It's likely parasites can alter our genetic expression and behavior today as well like rabies and toxoplasmosis(cats often have it). Rabies causing the fear of water is truly mind bending, how does it do that?! Toxoplasma infection is classically associated with the frequency of schizophrenia, suicide attempts or "road rage". https://pubmed.ncbi.nlm.nih.gov/31980266/#:~:text=Toxoplasma%20infection%20is%20classically%20associated,attempts%20or%20%22road%20rage%22 https://pubmed.ncbi.nlm.nih.gov/31980266/#:~:text=Toxoplasma.... Rabies:As the disease progresses, the person may experience delirium, abnormal behavior, hallucinations, hydrophobia (fear of water), and insomnia. https://www.cdc.gov/rabies/symptoms/index.html#:~:text=As%20the%20disease%20progresses%2C%20the,and%20treatment%20is%20typically%20supportive https://www.cdc.gov/rabies/symptoms/index.html#:~:text=As%20....
- whizzter 4y ago
  Even more interesting reverse of that, hairworms that infect grasshoppers will once mature cause the hosts to jump into water and drown where the worm then reproduces before starting the cycle again.
  - hypertele-Xii 4y ago
    And cordyceps fungi compel ants to climb to a specific height off ground, at millimeter and 95% accuracy, to a spot of ideal location and humidity for the fungus to spore. And the craziest thing is, the cordyceps fungus doesn't actually infiltrate the ant's brain! Autopsies found the fungus spreads all over the ant's body, but not its brain!
    - borissk 4y ago
      Have you seen the documentary that came this year, think it's called "Last Of Us" - fungus can turn humans into zombies :) But yeah, fungus directly controlling ant muscles, while it's brain is helpless is quite terrifying. Also terrifying is the raise of fungus infections in humans recorded in hospitals in India and UK in the recent years. If they do adapt to living in a warm human body we will have a major problem - fungus are killing more trees, bugs and reptiles than viruses and bacteria combined, the air in our cities is full of their spores.
mmmrtl 4y ago
Misleading title ("Their" Genes). I don't see what introners have to do with the human genome?? They found evidence for introners in 5% of species... Original paper: https://www.pnas.org/doi/10.1073/pnas.2209766119 https://www.pnas.org/doi/10.1073/pnas.2209766119
elevaet 4y ago
I might have missed it, but they didn't really discuss how introners replicate. Does the host species accidentally transcribe the intron segments into new introners until it evolves a mechanism to avoid that particular trick?
- photochemsyn 4y ago
  It's really just a proposal, there would have to be some associated enzyme that targets genes at the well-known splice site (maybe something like a CRISPR-related Cas etc. enzyme?)and inserts the intron sequence. This seems to date from this 2012 study: > "Birth of new spliceosomal introns in fungi by multiplication of introner-like elements (2012)" https://pubmed.ncbi.nlm.nih.gov/22658596/ https://pubmed.ncbi.nlm.nih.gov/22658596/ These are postulated to be relatively rare events, so catching one in the act would be difficult: > "However, dating of multiplication events showed that they degenerate in sequence and length within 100,000 years to eventually become indistinguishable from RSIs. We suggest that ILEs not only account for intron gains in six fungi but also in ancestral eukaryotes to give rise to most RSIs by a yet unknown multiplication mechanism." [ILE's being closely related intron sequences, RSIs being the regular jumbled-up types]

156 points by theafh 4y ago

Sometimes little frustrating that people writing articles in this field seem to have no exposure to computer science. This is the gene equivalent of a filesystem: the DNA fragments are like disk blocks. The interposing sections are file metadata. The shearing mechanism is the filesystem reconstructing a stream from the lower layer blocks. There's probably some redundancy and error correction in there too. It needs a filesystem for the same reason they were invented for computers: to provide an impedance match between the upper layer semantics (a stream of pairs describing a protein) and the lower layer storage (blocks). Using block structured storage is more flexible in terms of being able to insert in the middle of a file, etc etc.

monocasa 4y ago
I don't think that's a great comparison. Exons already have sequences that mark 'block' boundaries; amino acids are encoded in triplets of base pairs, but sort of like you see in 8b/10b encoding, there are sequences that are valid but only used for control purposes and don't correspond to amino acids.
rco8786 4y ago
That's a weird thing to get frustrated about...that someone in a completely unrelated field didn't have the experience or courtesy to explain something using analogous terms to the thing you happen to be an expert on.
- aeonik 4y ago
  I don't think they are unrelated fields. Computer science is the study of computation. DNA, to me, is clearly a quaternary computation system. I think there is a lot for both fields to learn by studying knowledge from each. Bioinformatics seems to be on that track.
  - anonymouskimmer 4y ago
    We've got DNA which is basically a storage system. RNA can be catalytically active on its own. Typically RNA and proteins, or complexes of such, act on DNA in various manners. Maybe you're right in some way, but also consider whether using the nomenclature and ideas used to described processes of DNA repair, transcription, and translation in biology to describe electronic computation works well. If it does work well, then maybe the reverse would also work well. If it leaves much to be desired, then consider the possibility that computer science ideas may be too specific to electronic or mechanical computation.
  - rco8786 4y ago
    Cool so what's the last thing you described to your team using terms from DNA research?
    - spullara 4y ago
      genetic optimization algorithms?
- vkou 4y ago
  Doubly so, when the two domains don't actually map cleanly to eachother. DNA is not a computer program, or a file, or storage. There's no real distinction between data, metadata, and 'code' in it, either in structure, or in practice.
afavour 4y ago
I don’t want to sound dense here but why is it frustrating that people who write about genetics aren’t familiar with computer science?
- agumonkey 4y ago
  I can have similar thoughts at times. People in one field have their own lens to see the world and might miss some structures / patterns that exist in other domains. I felt it was a bit pompous to read a few medical books about the cardiovascular system, a lot of ceremony to describe an organic pump. You'd have to read mathematically inclined papers to start reading about equations and principles rather than latin nomenclature. Which I think is what the grandparent was wishing for. ps: I absolutely do not put computing above other fields though. I just wish for some pragmatic polymathism sometimes.
- elchief 4y ago
  I suppose because they spent 6-8 years of their early adult lives focusing exclusively on biology and not computer science
sorokod 4y ago
It needs a filesystem for the same reason they were invented for computer Why would that be true? It is a cool analogy but implying that it is the reason requires much more.
- renewiltord 4y ago
  Without taking a stance on whether it's right, I believe that is explained right after your quote cut-off.
  - sorokod 4y ago
    That the biology of processing DNA is subject to similar constraints and solutions computer have dealing with disk storage is remarkable. Justification is needed.
    - bronson 4y ago
      At a coarse level, both are affected by information theory, so some parts may look vaguely similar. Sure, it’s plausible you’d find related solutions, especially if you really squint. But it’s like trying to explain how atoms work using a solar system analogy. It might help with the really easy stuff, maybe? (orbitals) But sticking with it makes going any deeper pretty confusing.
kleer001 4y ago
https://en.wikipedia.org/wiki/Curse_of_knowledge https://en.wikipedia.org/wiki/Curse_of_knowledge
otherme123 4y ago
There are organisms with almost no introns, no redundancy, no CRC, no "metadata" and even overlapping genes to save space, like Giardia genome ( https://www.science.org/doi/10.1126/science.1143837 https://www.science.org/doi/10.1126/science.1143837 ). Lots of virus have all their genes encoded without introns, and almost all the genome is encoding something. I've never seen DNA as close to a filesystem, and our current best bet on introns functions are they are used to create alternative splicing products from the same DNA chunk. I cannot identify this function in a filesystem, where you can obtain two or three different valid files from the same data just by skipping some blocks.
- pazimzadeh 4y ago
  What is CRC? Metadata is everywhere... histone modifications, glycosylation, etc..
  - anonymouskimmer 4y ago
    Cyclic redundancy check? And there is almost always basic redundancy in non-viral organisms (and many viruses) in that DNA is typically double-stranded, and most organisms have repair machinery that can rewrite across single-strand lesions using the opposite strand (this fails at double-strand lesions).
- GauntletWizard 4y ago
  I can - It's called COW Snapshotting. Modern filesystems like ZFS and BTRFS don't ever overwrite parts of the file that change. They abstract it away by keeping an ordered list of blocks. Snapshots are simply copies of the old list. The analogy doesn't go very far, however.
  - bronson 4y ago
    COW just dedupes, it doesn’t produce alternatives. Maybe a filesystem that figures out how your spreadsheet can be stored partway into an executable, with no loss to either? Yeah, this analogy doesn’t seem real helpful.
  - 4y ago
deleted 4y ago
[deleted]
inciampati 4y ago
I don't like appeals to authority, but as a computational biologist, I am both a computer scientist and a biological scientist. So understand that I'm responding to you as exactly the kind of person you think should be drawing the kinds of links that you're suggesting. I'm sorry, but this is just not a reasonable analogy. DNA sequences are not like computer files. The reason that they're distinct modules in these sequences is due to the need for evolution to be feasible. And also for the basic reason that the sequences are linear and so modules tend to appear in these linear sequences. But there also tremendous nonlinearities as well. Things at very long distances can be importantly related to each other. The introns are not metadata. There are regions that can be removed selectively and in combinations to cause diversity in the produced proteins. That diversity is advantageous because it allows a single DNA sequence to present many different proteins that are typically related, but can be very different structurally. This splicing capability has evolved apparently from entities that can be seen as endogenous viruses or DNA parasites that have the ability to insert and splice themselves out of DNA and RNA sequences. In many confusing words, that's what the article or pointing at is talking about. The introns do provide a kind of redundancy, but only in the sense that there are areas that can be modified with minimal effect on cellular function, at least relative to modification of the exons, which directly correspond in a one to one way with proteins. There is error correction. It's called homologous chromosomes. Everyone talks about there being one genome, but in most complex forms of life, you have more than one copy per cell, usually two, and often more. These multiple copies, in addition to allowing for recombination and sexual reproduction, provide templates on which errors which arise during life can be corrected. However, there are no error correcting codes. If you'd like to learn more about the actual details of these systems, I strongly suggest an undergraduate molecular biology textbook. The best one in existence is called the Molecular Biology of the Cell. There are indeed many similarities between computing systems and biological systems, but the analogies you are making don't appear to be clear. Read a book like this, deeply and slowly, and it might change your life. At very least, it'll mean that the world you live in is much less mysterious and much more exciting.
- pazimzadeh 4y ago
  Aren't introns like pieces of code that have been commented out? But they also change the 3D conformation of the DNA itself, which changes access by transcription factors, etc.
gus_massa 4y ago
You look interested in the subject, but I recommend to read a few biology books about it. There are many weird low level features of DNA that are not so cover in popular discussions [1] [2]. But I don't remember any that is similar to a filesystem as you propose. Take a look, you will be gladly surprised. [1] One of my favorites is that the bases of ADN are translated in groups of 3 to amino acids, so the code reads like AAABBBCCCDDDEEEFFF It's very unusual, but there are some virus that read the same part in two ways, with different offset, so the same part is interpreted as -JJJKKKLLLMMMNNN-- I don't remember if they use the other offset too --PPPQQQRRRSSSTTT- [2] Another, not so interesting but relevant. Eukaryote has linear DNA, so they have some special repetition in the extremes. The idea is that the extremes are difficult to copy by the usual enzyme that copy the main part that has assorted code. But the extremes have a special easy pattern, so the cell can use some specialized enzyme to make them longer.
bashinator 4y ago
Nope, at best the filesystem is an analogy. Just like the stretchy rubber mat isn't a perfect description of spacetime.
anonymouskimmer 4y ago
> It needs a filesystem for the same reason they were invented for computers: to provide an impedance match between the upper layer semantics (a stream of pairs describing a protein) and the lower layer storage (blocks). Using block structured storage is more flexible in terms of being able to insert in the middle of a file, etc etc. As a non-CS person I find this explanation opaque.
AllegedAlec 4y ago
https://xkcd.com/793/ https://xkcd.com/793/

fnordpiglet 4y ago

I for one welcome our new introner overlords.

MagicMoonlight 4y ago

That’s sneaky. Ironically more like a computer virus than the classical viruses. Taking over the host and modifying its boot partition so that it permanently gets produced by the system.

anonymouskimmer 4y ago
There's basically no such thing as a boot partition. The machine of life has been turned on since the beginning. At this point, with all of the changes since the beginning, it's not obvious that there's a "boot partition" left that could reactivate life should it shut off. All cellular progeny is made with already functional and switched on proteins and RNA. The best you get to shutting off (without permanent cell death) would be the computer equivalent of hibernation. All the proteins and RNA are still there just waiting for the signal to activate again.
- jamiek88 4y ago
  Crazy to think we are all here because of that first multi cellular organism splitting over and over and over. Life doesn’t reboot as you say, it is split off from other organisms whether seed, sperm, rhizome or any other method it’s just cells dividing and spitting off other cells. Mind boggling to me.
  - anonymouskimmer 4y ago
    Yeah. I've known this for years but it really struck me when I typed it out here.
  - __MatrixMan__ 4y ago
    The idea that we all branched from a single ancestral organism has never sat well with me. Whatever started that process, however improbable... Well the universe allowed it to happen. Why expect that the universe wouldn't subsequently continue to let it happen, again and again?
    - 4y ago

masswerk 4y ago

"spliceosomes" – I'm somewhat disappointed. (Not really the true greco-roman spirit.)

fjfaase 4y ago

Bert Hubert has an interesting idea about the reasons for interons. He explains this in his talk 'DNA: More Greatest Hits (SHA2017)' The interesting bit, with some introduction, starts at: https://youtu.be/rCdhsN--Mdo?t=1440 https://youtu.be/rCdhsN--Mdo?t=1440 This is a follow-up talk to his talk: 'DNA: The Code of Life' https://www.youtube.com/watch?v=EcGM_cNzQmE https://www.youtube.com/watch?v=EcGM_cNzQmE

neoyagami 4y ago

oh. a "descolada"

elevaet 4y ago
Care to explain what you mean here?

deleted 4y ago

[deleted]

koeng 4y ago

My favorite quote I saw or heard somewhere on the rogue genetic elements in us all: “We are but a raft of genes in an ocean of retrotransposons” A little hyperbolic, but dang there are a lot

stuckinhell 4y ago

Biology is truly fascinating, the ultimate hardware/software combo of proteins/genes. It's likely parasites can alter our genetic expression and behavior today as well like rabies and toxoplasmosis(cats often have it). Rabies causing the fear of water is truly mind bending, how does it do that?! Toxoplasma infection is classically associated with the frequency of schizophrenia, suicide attempts or "road rage". https://pubmed.ncbi.nlm.nih.gov/31980266/#:~:text=Toxoplasma%20infection%20is%20classically%20associated,attempts%20or%20%22road%20rage%22 https://pubmed.ncbi.nlm.nih.gov/31980266/#:~:text=Toxoplasma.... Rabies:As the disease progresses, the person may experience delirium, abnormal behavior, hallucinations, hydrophobia (fear of water), and insomnia. https://www.cdc.gov/rabies/symptoms/index.html#:~:text=As%20the%20disease%20progresses%2C%20the,and%20treatment%20is%20typically%20supportive https://www.cdc.gov/rabies/symptoms/index.html#:~:text=As%20....

whizzter 4y ago
Even more interesting reverse of that, hairworms that infect grasshoppers will once mature cause the hosts to jump into water and drown where the worm then reproduces before starting the cycle again.
- hypertele-Xii 4y ago
  And cordyceps fungi compel ants to climb to a specific height off ground, at millimeter and 95% accuracy, to a spot of ideal location and humidity for the fungus to spore. And the craziest thing is, the cordyceps fungus doesn't actually infiltrate the ant's brain! Autopsies found the fungus spreads all over the ant's body, but not its brain!
  - borissk 4y ago
    Have you seen the documentary that came this year, think it's called "Last Of Us" - fungus can turn humans into zombies :) But yeah, fungus directly controlling ant muscles, while it's brain is helpless is quite terrifying. Also terrifying is the raise of fungus infections in humans recorded in hospitals in India and UK in the recent years. If they do adapt to living in a warm human body we will have a major problem - fungus are killing more trees, bugs and reptiles than viruses and bacteria combined, the air in our cities is full of their spores.

mmmrtl 4y ago

Misleading title ("Their" Genes). I don't see what introners have to do with the human genome?? They found evidence for introners in 5% of species... Original paper: https://www.pnas.org/doi/10.1073/pnas.2209766119 https://www.pnas.org/doi/10.1073/pnas.2209766119

elevaet 4y ago

I might have missed it, but they didn't really discuss how introners replicate. Does the host species accidentally transcribe the intron segments into new introners until it evolves a mechanism to avoid that particular trick?

photochemsyn 4y ago
It's really just a proposal, there would have to be some associated enzyme that targets genes at the well-known splice site (maybe something like a CRISPR-related Cas etc. enzyme?)and inserts the intron sequence. This seems to date from this 2012 study: > "Birth of new spliceosomal introns in fungi by multiplication of introner-like elements (2012)" https://pubmed.ncbi.nlm.nih.gov/22658596/ https://pubmed.ncbi.nlm.nih.gov/22658596/ These are postulated to be relatively rare events, so catching one in the act would be difficult: > "However, dating of multiplication events showed that they degenerate in sequence and length within 100,000 years to eventually become indistinguishable from RSIs. We suggest that ILEs not only account for intron gains in six fungi but also in ancestral eukaryotes to give rise to most RSIs by a yet unknown multiplication mechanism." [ILE's being closely related intron sequences, RSIs being the regular jumbled-up types]