7 ms·

We really seem to know extraordinarily little about how our bodies work apart from physical mechanics & electrical activity. I can't even put a % on the rest ex

We really seem to know extraordinarily little about how our bodies work apart from physical mechanics & electrical activity. I can't even put a % on the rest except that we have barely scratched the surface. From epigenetics to the brain, metabolism, and immune system, we have a long way to go. On the other hand, we've probably made more progress in that understanding during the past 100 years than in all of the time before that. So, if our rate of knowledge acquisition is increasing, maybe that upward hill isn't quite so steep.

amelius 5y ago
Things can really speed up once we have robots that grow cells and perform experiments on them, and collect (big) data and automatically analyze the data.
- asdff 5y ago
  People already can grow up billions of cells for experiments and use supercomputers to process terabytes of sequencing data with statistical modelling. The hard part isn't the scale, but designing experiments and figuring out what evidence is needed to answer specific biological questions. That stuff you can't speed up with robotic arms and more processor cores, it takes time for people to think about these things and have conversations with others about these topics.
  - EamonnMR 5y ago
    Not to mention the amount of time experiments take-suppose we want to know if a drug prevents an illness that takes decades to develop? Sure you can model it in a mouse, but to do that you need to know exactly what the parameters of your model are.
  - amelius 5y ago
    I'm not so sure about that. For example, with robots you can run "for GENE in GENOME do ..." For humans even thinking about what that statement does is a lot of work already!
    - mythrwy 5y ago
      It's not a one dimensional problem though. There is a lot of interaction between the various systems in a human body. To keep with the programming analogy, ya, you can see the SUM statement and that is necessary to understand, but what is it for? What is it's role in the larger program? Where do it's inputs come from? Where do they go? What effect does changing it have in other places? I do agree our knowledge of genetics etc. will be much expanded soon. But we'll probably also make some nasty errors.
      - amelius 5y ago
        > There is a lot of interaction between the various systems in a human body. Yes, the interactions are the interesting bit. Perhaps we can figure out the biological pathways at the cellular level by taking a systematic approach of turning genes on/off and turning their expression on/off, then looking at the expression of other genes. This is exactly what could be done by robots.
        ethanbond 5y ago
        I think you’re seriously underestimating the scale of the genome and the number of possible combinations that might be responsible for some phenotype, even assuming the genotype -> phenotype causality was straightforward (which it’s not). This is simply not a problem we’re going to computer our way through, at least until we have large scale quantum computers and way better data than we have today.
        jcims 5y ago
        Naively, a small protein of ~100 amino acid residues has ~21^100 configurations. Amino acids average 110 Daltons each (110g/mol), you would need approximately 3*10^107kg of matter to build them all. There is an estimated 10^53kg of matter in the known universe.
- ezconnect 5y ago
  The problem is how do we sense and measure them. Once we invent the methods of sensing, measuring and observing a single process we need a million more for the other process and that takes time.
  - amelius 5y ago
    There are various techniques for that. For example with RNAseq you can measure which genes are expressed as a result of an experiment.
jes 5y ago
I was having a discussion with a friend yesterday and we got onto the topic of vaccinations. To my knowledge, while we can develop a statistical assessment of a vaccine's safety, we can never know how the vaccine will affect a specific person that takes it. My argument here is that the human body is so fantastically complex that no two cases are ever the same, and so the only way to know how a vaccine will affect a person is to run the experiment, by having them take it. I think this is one attribute of what are called "Wicked Problems": The only way to know if a change is going to be an improvement or not is to make the change and see how the system state evolves forward in time. Is this roughly correct?
- dd36 5y ago
  Evolution says hi. I like Kevin Kelly’s technium concept. We are merely an extension of evolution and our purpose is to continue it, which we do willingly and unwillingly.
- teekert 5y ago
  Not really, we can test a drug on a large population and determine it to be effective on 5% of all people. With no further info you know you have about a 5% chance of getting better. With more research we may determine that for people with a specific variant in their DNA the succes rate is 60%, so you can be part of two groups. We can keep making it better, maybe never 100% but very from “a gamble”. Would you say that hopping on a plane is an experiment in testing if it will crash? When you know it very likely will not?
  - Vrondi 5y ago
    Your plane analogy would only work if every passenger had a unique plane due to genetics, epigentics, etc.
    - teekert 5y ago
      I’d say it’s more like we have a lot of similar genetics (the plane) and then some small differences (the seat you are in) but yeah the analogy is a stretch, “similar” is not really a quantitative term but I think you are assuming we are more different then we really are. But that also varies per parameter. For example there is a reason we test drugs on mice, because they are pretty similar to us (mammals), of course there are also differences.
grishka 5y ago
Well, once we discover a way to prevent or reverse aging, everything else would be a matter of time, of which you would now have an effectively unlimited amount.
- pdm55 5y ago
  I have never believed the argument that we can develop a way to live to 200. I am now in my mid 60s and it seems that a number of my parts are starting to "wear out". My skin is certainly thinner; my eyesight is damaged (macula degeneration) in one eye; ... And covid has taught us that our immune systems are not as effective as when we were younger. We older folks all see heart and cancer problems over the horizon. Cancer just seems a matter of time: I mean how can our cells keep replicating the 3 billion(?) base pairs in our genomes - with a mistake rate of about 1 per 100 000 (i.e. 30k mistakes per division) - without those eventually leading to cancer? And if I could only remember how to spell that alzyhmr thing, I would mention it also. And why does our government keep sending me those kits for faeces samples? Sorry to disagree with you, but I don't think aging is a reversible process: we seem to have too many parts, each with an "expiry date".
  - finolex1 5y ago
    Not a biologist, but certain sharks, whales and tortoises have been known to live for >150 years, so I suppose it is theoretically possible.
    - ejolto 5y ago
      Greenland shark reach sexual maturity at 150 years, and can live for over 400 years according to Wikipedia.
  - dwohnitmok 5y ago
    The main reason why it seems like it's not just a matter of "parts wearing out" is that different animals all age at different rates, but strikingly they all seem to age in similar ways. For example while dogs have a much shorter lifespan than humans they seem to face all the same age-related declines humans face. This holds for animals close to or exceeding our mass as well. If different parts of the body wore out simply due to e.g. mechanical stress, you would expect e.g. dog joints to be perfectly healthy after 15 years since they are biologically very similar to human joints, when in fact dogs tend to still have arthritic and otherwise fragile joints at 15 (or earlier). Everything declining together, just on different timetables in different animals, seems to suggest that aging is controlled by either a single mechanism or some interwoven set of mechanisms that cause everything to fail at the same time, rather than individual parts failing because "they wear out." If you could target that mechanism(s) then maybe you can make humans live as long as e.g. tortoises. But of course we haven't confirmed that such things exist, but the above is at least some motivation for why they might exist.

amelius 5y ago

Things can really speed up once we have robots that grow cells and perform experiments on them, and collect (big) data and automatically analyze the data.

asdff 5y ago
People already can grow up billions of cells for experiments and use supercomputers to process terabytes of sequencing data with statistical modelling. The hard part isn't the scale, but designing experiments and figuring out what evidence is needed to answer specific biological questions. That stuff you can't speed up with robotic arms and more processor cores, it takes time for people to think about these things and have conversations with others about these topics.
- EamonnMR 5y ago
  Not to mention the amount of time experiments take-suppose we want to know if a drug prevents an illness that takes decades to develop? Sure you can model it in a mouse, but to do that you need to know exactly what the parameters of your model are.
- amelius 5y ago
  I'm not so sure about that. For example, with robots you can run "for GENE in GENOME do ..." For humans even thinking about what that statement does is a lot of work already!
  - mythrwy 5y ago
    It's not a one dimensional problem though. There is a lot of interaction between the various systems in a human body. To keep with the programming analogy, ya, you can see the SUM statement and that is necessary to understand, but what is it for? What is it's role in the larger program? Where do it's inputs come from? Where do they go? What effect does changing it have in other places? I do agree our knowledge of genetics etc. will be much expanded soon. But we'll probably also make some nasty errors.
    - amelius 5y ago
      > There is a lot of interaction between the various systems in a human body. Yes, the interactions are the interesting bit. Perhaps we can figure out the biological pathways at the cellular level by taking a systematic approach of turning genes on/off and turning their expression on/off, then looking at the expression of other genes. This is exactly what could be done by robots.
      - ethanbond 5y ago
        I think you’re seriously underestimating the scale of the genome and the number of possible combinations that might be responsible for some phenotype, even assuming the genotype -> phenotype causality was straightforward (which it’s not). This is simply not a problem we’re going to computer our way through, at least until we have large scale quantum computers and way better data than we have today.
        jcims 5y ago
        Naively, a small protein of ~100 amino acid residues has ~21^100 configurations. Amino acids average 110 Daltons each (110g/mol), you would need approximately 3*10^107kg of matter to build them all. There is an estimated 10^53kg of matter in the known universe.
ezconnect 5y ago
The problem is how do we sense and measure them. Once we invent the methods of sensing, measuring and observing a single process we need a million more for the other process and that takes time.
- amelius 5y ago
  There are various techniques for that. For example with RNAseq you can measure which genes are expressed as a result of an experiment.

jes 5y ago

I was having a discussion with a friend yesterday and we got onto the topic of vaccinations. To my knowledge, while we can develop a statistical assessment of a vaccine's safety, we can never know how the vaccine will affect a specific person that takes it. My argument here is that the human body is so fantastically complex that no two cases are ever the same, and so the only way to know how a vaccine will affect a person is to run the experiment, by having them take it. I think this is one attribute of what are called "Wicked Problems": The only way to know if a change is going to be an improvement or not is to make the change and see how the system state evolves forward in time. Is this roughly correct?

dd36 5y ago
Evolution says hi. I like Kevin Kelly’s technium concept. We are merely an extension of evolution and our purpose is to continue it, which we do willingly and unwillingly.
teekert 5y ago
Not really, we can test a drug on a large population and determine it to be effective on 5% of all people. With no further info you know you have about a 5% chance of getting better. With more research we may determine that for people with a specific variant in their DNA the succes rate is 60%, so you can be part of two groups. We can keep making it better, maybe never 100% but very from “a gamble”. Would you say that hopping on a plane is an experiment in testing if it will crash? When you know it very likely will not?
- Vrondi 5y ago
  Your plane analogy would only work if every passenger had a unique plane due to genetics, epigentics, etc.
  - teekert 5y ago
    I’d say it’s more like we have a lot of similar genetics (the plane) and then some small differences (the seat you are in) but yeah the analogy is a stretch, “similar” is not really a quantitative term but I think you are assuming we are more different then we really are. But that also varies per parameter. For example there is a reason we test drugs on mice, because they are pretty similar to us (mammals), of course there are also differences.

grishka 5y ago

Well, once we discover a way to prevent or reverse aging, everything else would be a matter of time, of which you would now have an effectively unlimited amount.

pdm55 5y ago
I have never believed the argument that we can develop a way to live to 200. I am now in my mid 60s and it seems that a number of my parts are starting to "wear out". My skin is certainly thinner; my eyesight is damaged (macula degeneration) in one eye; ... And covid has taught us that our immune systems are not as effective as when we were younger. We older folks all see heart and cancer problems over the horizon. Cancer just seems a matter of time: I mean how can our cells keep replicating the 3 billion(?) base pairs in our genomes - with a mistake rate of about 1 per 100 000 (i.e. 30k mistakes per division) - without those eventually leading to cancer? And if I could only remember how to spell that alzyhmr thing, I would mention it also. And why does our government keep sending me those kits for faeces samples? Sorry to disagree with you, but I don't think aging is a reversible process: we seem to have too many parts, each with an "expiry date".
- finolex1 5y ago
  Not a biologist, but certain sharks, whales and tortoises have been known to live for >150 years, so I suppose it is theoretically possible.
  - ejolto 5y ago
    Greenland shark reach sexual maturity at 150 years, and can live for over 400 years according to Wikipedia.
- dwohnitmok 5y ago
  The main reason why it seems like it's not just a matter of "parts wearing out" is that different animals all age at different rates, but strikingly they all seem to age in similar ways. For example while dogs have a much shorter lifespan than humans they seem to face all the same age-related declines humans face. This holds for animals close to or exceeding our mass as well. If different parts of the body wore out simply due to e.g. mechanical stress, you would expect e.g. dog joints to be perfectly healthy after 15 years since they are biologically very similar to human joints, when in fact dogs tend to still have arthritic and otherwise fragile joints at 15 (or earlier). Everything declining together, just on different timetables in different animals, seems to suggest that aging is controlled by either a single mechanism or some interwoven set of mechanisms that cause everything to fail at the same time, rather than individual parts failing because "they wear out." If you could target that mechanism(s) then maybe you can make humans live as long as e.g. tortoises. But of course we haven't confirmed that such things exist, but the above is at least some motivation for why they might exist.