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The human genome is full of viruses

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Re: The human genome is full of viruses

#51
post #15

Earlier quoted context omitted.

> I've always wondered how such a relatively small amount of data could describe the massive complexity of a full-size organism I'm not convinced it fully does. Remember that DNA is never in isolation; there's always a cell that's been replicated and passed down to offspring, so there's interplay between the hardware cell and software DNA. I also don't know much about biology and only took a high school class, so don…

I think what you’re describing here is called “epigenetics,” or how different genes are expressed or not expressed due to environmental and other outside factors such as stress, etc...

What GP is talking about is that information is never fully contained in a medium; it's encoded in the tuple (the medium, what reads the medium). E.g. take a JPG file. The picture in that file isn't fully contained in the bits that file consists of. Some of the information is contained in the JPG specification (and through it, in the JPG decoding library). You need both to get at the picture. Meanwhile, with a different decoding program, the same file can represent a piece of music. Or a text document.

"Gödel, Escher, Bach" goes into a detailed discussion about this.

On top of that, GP is talking about hardware that builds its own copies, possibly imperfect copies. That implies a lot of information relevant to the organism may not be directly visible in the DNA - it may sit within the replication machinery, and evolve there. It's kind of similar to the difference between machine code and microcode + actual traces in silicon.

A famous Turing Award Lecture by Ken Thompson, "Reflections on Trusting Trust", provides another example[0]. Consider a C compiler. How do you build one? From its C source code, using a different C compiler. Now imagine a malicious C compiler that a) injects a trojan into the compiled binary whenever it compiles, say, "login" program, and b) injects a trojan into the binary whenever it compiles another C compiler; that second trojan contains the code for injecting a) and b). You use that compiler to recompile the original C compiler, install it in a system - and from now on, not only "login" will be bugged, but you can't get a non-malicious compiler by recompiling the original one from source; the source contains no traces of the trojans, but they are there, in the binary of the compiler you're using, and they self-replicate.

This is what I believe happens with life.

--

[0] - https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...

Re: The human genome is full of viruses

#53

> Even after recovering from an infection there will always be a piece of that virus encoded within your DNA. I did a little research and this appears to be almost completely false . This sentence makes it sound like every time you get a cold, your body's DNA is permanently altered. Which would be insane if true. The reality is that this insane outcome is incredibly rare, but nevertheless has happened enough times ov…

The author of this article is a philosopher promoting a book and not a scientist.

Re: The human genome is full of viruses

#54
post #31
post #12

Earlier quoted context omitted.

You can't bootstrap a cell from DNA - you need a functioning cell to start with. There's a lot of semantic data that's embodied in the existing set of proteins and other functional elements, and I don't think it's clear that the DNA of any moderately complex organism actually expresses that state.

You can't bootstrap a self-hosting compiler from a language you just made up either. You'll need to first write a compiler in another language then use it to compile the compiler you wrote in your new language. I think the compiler/program dichotomy is a more apt metaphor for cells and dna than the computer /program one.

See https://news.ycombinator.com/item?id=22515015, in particular the "Reflections on Trusting Trust". You can bootstrap your target language from almost nothing by incrementally compiling more complex compilers, and all the intermediary complexity is stored in the compiler, not in the source code of the language you're trying to bootstrap. Notably, life did proceed like this - incrementally, from the first replicator.

(Another way to look at it: a piece of code, be it DNA or a program written in a programming language, is just a bunch of symbols. You can't divine what these symbols mean from looking at the piece of code alone; you have to understand the mechanics of your compiler and your runtime. And these can evolve separately to the code you're looking at.)

Re: The human genome is full of viruses

#55
post #3

I've always thought of DNA as mere "data". "This goes here, that goes there", etc. And I've always wondered how such a relatively small amount of data could describe the massive complexity of a full-size organism. But this makes it sound like DNA is data the way Lisp is data: it can contain procedures and transformations and meta-statements about itself, and even mutate during the course of being interpreted. That wo…

Just in case this is not known, human generic code is more than just DNA. Most important parts of what encodes us are: - DNA - epigenetic markers on the DNA which modulate which parts of the DNA are active. You influence these and pass them on to your children (as men) and grandchildren (as women, as girls are born with all egg cells they'll ever have) - cell organelles which copy the DNA, ensure the cell has food an…

DNA isn’t data, or even code. DNA is a machine that builds things.

Re: The human genome is full of viruses

#57
> A biological virus (whether it is a true virus, an endogenous retrovirus, or a transposon) can literally lay dormant in a word document as a string of As, Ts, Cs, and Gs.

Literally, huh? In a word document?

Re: The human genome is full of viruses

#58
post #57

> A biological virus (whether it is a true virus, an endogenous retrovirus, or a transposon) can literally lay dormant in a word document as a string of As, Ts, Cs, and Gs. Literally, huh? In a word document?

Sure, that's why we get the usual advice:

- wash your hands with soap as often as possible

- do not touch your mouth, nose, or eyes when outside

- always disable macros in word and excel

Re: The human genome is full of viruses

#59

> Even after recovering from an infection there will always be a piece of that virus encoded within your DNA. I did a little research and this appears to be almost completely false . This sentence makes it sound like every time you get a cold, your body's DNA is permanently altered. Which would be insane if true. The reality is that this insane outcome is incredibly rare, but nevertheless has happened enough times ov…

> Viruses [...]have circadian rhythms like all living things.

> circadian adj. of, relating to, or showing rhythmic behaviour with a period of 24 hours; especially of a biological process

No, they don't.

And the rest of the paragraph is equally goofy.

Re: The human genome is full of viruses

#60
post #45

> Even after recovering from an infection there will always be a piece of that virus encoded within your DNA. I did a little research and this appears to be almost completely false . This sentence makes it sound like every time you get a cold, your body's DNA is permanently altered. Which would be insane if true. The reality is that this insane outcome is incredibly rare, but nevertheless has happened enough times ov…

If it was true then presumably we'd see the DNA of identical twins diverging with age (proxy for number of infections). Do we?

This happens even from just spontaneous mutations. The body has many copies of DNA and they are not in sync with each other. Your cells diverge from your twins' cells, but also from each other.
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