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This is a wild misstatement of what is going on. Morphogenesis is primarily governed by chemical interactions between proteins, on cell surfaces and secreted in
by twic 4y ago
This is a wild misstatement of what is going on. Morphogenesis is primarily governed by chemical interactions between proteins, on cell surfaces and secreted into intercellular space, as has been studied for decades:
https://en.wikipedia.org/wiki/Developmental_biology https://en.wikipedia.org/wiki/Developmental_biology
And the proteins, and the maps and schedules for their production, and the machinery which gives them effect, are all encoded in the DNA.
I haven't actually followed Levin's recent work, so i don't know if he's going round actively misleading people about this, or if people are hearing about his work and assuming that's the whole story. To be honest, from what i've heard, he seems like a crank.
- bglazer 4y agoI don’t think Levin is a crank. He went on Lex Fridman’s podcast and talked about his bioelectricity work and morphogenesis. Like you said, I think people who don’t know much about development took that to be the whole story, when in reality it’s just one academic doing what academics do best: talk about their own work. Edit: one small quibble with your comment is that it’s too reductive to say that morphogenesis is all encoded in the DNA. It’s really an emergent property of the whole system. Like DNA is only a few billion base pairs, which is not nearly enough to store the precise positions of every cell, much less every protein.
- twic 4y agoThanks, this makes sense. I think my reduction and your quibble is really a matter of semantics. It's true that the genome doesn't contain explicit coordinates for every feature of every cell. But at the same time, if you start with the same DNA, you get the same morphogenesis, and if you start with different DNA, you get different morphogenesis, so i would say the morphogenesis is very much encoded in the DNA. It's just that it's in a highly compressed representation, and the decompression machinery includes the laws of physics!
- swamp40 4y ago> if you start with the same DNA, you get the same morphogenesis Then how do you explain their creation of xenobots using only frog DNA? That was the whole point of the experiment - to disprove your statement. https://wyss.harvard.edu/news/team-builds-first-living-robots-that-can-reproduce/ https://wyss.harvard.edu/news/team-builds-first-living-robot...
- twic 4y agoOkay, same DNA in the same context then. That experiment doesn't disprove it in the slightest. Indeed, the fact that the experiment is repeatable confirms it.
- bglazer 4y agoYeah sounds like we are both expressing the same idea. I’m usually pretty touchy about software analogies for biology but “decompression machinery includes the laws of physics” is a good way to frame it.