Unfortunately, inserting complex novel gene sequences into every cell of an organism in a way that doesn’t just cause massive, global cancer is very hard problem. Making those sequences do what you want them to do, and not, say, kill the target organism is even harder. Especially since human anatomy isn’t well suited to the task, and would need to be modified. By the time we have the technology to do something like that, death is probably already a solved problem.
That said, I’ve used the premise in a science fiction book before. The main characters were members of Homo Sapiens Durabilis, and had genomes modified with tardigrade genetics. They could be pumped full of hydrogen sulfide, and reversibly dehydrated to death for long-term space travel, or during a medical emergency.
I’m most familiar with gene therapy issues causing cancer, but that might be an availability bias—in those studies where gene therapy simply kills the relevant cells, I’m sure very little is published.
The traditional way of inserting a gene into the genome is to use a retrovirus with its DNA replaced. Most such viruses (at least, that have been used) incorporate randomly, meaning that there is a small but nonzero chance every time a new cell is modified that it will knock out a gene that is important for controlling cancer. On a cellular level, the most likely cause of this is cell death, as the rest of the cell’s anticancer mechanisms shut down the cell. But of course, this doesn’t work every time.
There are specific viruses (i.e. that always integrate at the same, safe genomic location) currently being developed, and it’s hoped that these will solve the problem.
However, there’s actually another related problem. If you want to make major changes to the cell (like reprogramming it into a stem cell), the cell’s anticancer mechanisms will detect that as well, so in order to make those changes you have to at least temporarily shut off some of those mechanisms. So there is a risk for cancer in that as well.
About the topic of this thread—generally, the ability to survive specific extreme environments (especially one that affects everything in the cell such as changes in water content or temperature) is a specialized adaptation. I would not be surprised if there are global differences in the genomes of these species, e.g. most proteins are much more hydrophilic, or there is a system of specialized chaperones (=proteins that refold other proteins or help prevent them from misfolding) plus the adaptations in proteins that allow the chaperones to act on them, and further systems to repair damage the chaperones don’t prevent. It is unlikely that only a few genes would be involved, and unless a case can be made for evolutionary conservation of the adapted genes to humans, we wouldn’t have most of them (in fact, any genome-wide changes would mean that we would have to adapt our own proteins in new ways, just because we don’t share all of them with the species in question). Cold temperature is actually a special case here, because it slows down everything and thus reduces the amount of “equivalent normal-temperature time” that has passed. It’s still difficult (and of course none of these are impossible), but I don’t think it’s likely that small-scale gene therapy would be sufficient.
The physical structure of the cells have to change. You also don’t see this sort of behavior in large organisms, so there may be serious engineering challenges with the dehydration mechanisms in large animals. You’re essentially going to need powerful, global, highly specific gene therapy at the bare minimum. It might not be possible without engineering a new organism from scratch.
That’s a fair question. I was assuming that creatures which can survive full dehydration are so different at the cellular level that nothing less than genetic redesign would do the job, but I’m guessing.
People die as the result of very moderate dehydration, so considerable change of some sort would be required.
It’s plausible that if dehydration and revival are possible for people, then the methods wouldn’t be much like what’s evolved—people don’t fly the same way birds do.
That’s a fair question. I was assuming that creatures which can survive full dehydration are so different at the cellular level that nothing less than genetic redesign would do the job, but I’m guessing.
I think part of the problem, too, is that animals who can survive full dehydration, or being thoroughly frozen within and without, are small. We don’t often realize just how big humans are, even for land-dwelling tetrapods. We’re very large, very active, and very resource-intensive—certainly there are bigger land animals about today and in our recent past, and very much bigger ones in the fossil record (brachiosaurs, anyone?), but even then we still qualify as megafauna.
The consequences of that size, especially in light of our activity level, are significant. Human physiology is very adapted to dissipate heat well (and our water intake is a big part of that), yet we still routinely have trouble doing it fast enough to avoid ill effects, forcing us to adapt culturally and individually to the problem. We have to conserve quantities (of temperature regulation, of water) at fairly specific levels; our physiology is critically dependent on them.
So, yeah—if people can be put in suspended animation of some sort (regardless of mechanism), it’s gonna have to take our particular case into account. You can flash-freeze a mouse, thaw it, and get biological activity after (they don’t exactly go on to live long and prosperous mousey lives, but they do come out the other side for a bit). A mouse is tiny; you can’t extend that to a human without different physics becoming relevant. You can dehydrate a tardigrade quickly (just let it do its thing in a low-moisture environment for long enough until it loses enough water) and then leave it sitting until it gets doused again; you can’t do that to a human, because we have a lot of water to lose, our bodies fight to hang on to it, our health declines rapidly as we lose even modest amounts, and we proceed straight to death once quantities are insufficient.
Unfortunately, inserting complex novel gene sequences into every cell of an organism in a way that doesn’t just cause massive, global cancer is very hard problem. Making those sequences do what you want them to do, and not, say, kill the target organism is even harder. Especially since human anatomy isn’t well suited to the task, and would need to be modified. By the time we have the technology to do something like that, death is probably already a solved problem.
That said, I’ve used the premise in a science fiction book before. The main characters were members of Homo Sapiens Durabilis, and had genomes modified with tardigrade genetics. They could be pumped full of hydrogen sulfide, and reversibly dehydrated to death for long-term space travel, or during a medical emergency.
By the way, what was the name of the book?
“Morse Code”. But it wasn’t working thematically, and I abandoned the project. I’ve written a few other stories in the same universe.
Why is global cancer the primary risk rather than not being viable at all?
I’m most familiar with gene therapy issues causing cancer, but that might be an availability bias—in those studies where gene therapy simply kills the relevant cells, I’m sure very little is published.
The traditional way of inserting a gene into the genome is to use a retrovirus with its DNA replaced. Most such viruses (at least, that have been used) incorporate randomly, meaning that there is a small but nonzero chance every time a new cell is modified that it will knock out a gene that is important for controlling cancer. On a cellular level, the most likely cause of this is cell death, as the rest of the cell’s anticancer mechanisms shut down the cell. But of course, this doesn’t work every time.
There are specific viruses (i.e. that always integrate at the same, safe genomic location) currently being developed, and it’s hoped that these will solve the problem.
However, there’s actually another related problem. If you want to make major changes to the cell (like reprogramming it into a stem cell), the cell’s anticancer mechanisms will detect that as well, so in order to make those changes you have to at least temporarily shut off some of those mechanisms. So there is a risk for cancer in that as well.
About the topic of this thread—generally, the ability to survive specific extreme environments (especially one that affects everything in the cell such as changes in water content or temperature) is a specialized adaptation. I would not be surprised if there are global differences in the genomes of these species, e.g. most proteins are much more hydrophilic, or there is a system of specialized chaperones (=proteins that refold other proteins or help prevent them from misfolding) plus the adaptations in proteins that allow the chaperones to act on them, and further systems to repair damage the chaperones don’t prevent. It is unlikely that only a few genes would be involved, and unless a case can be made for evolutionary conservation of the adapted genes to humans, we wouldn’t have most of them (in fact, any genome-wide changes would mean that we would have to adapt our own proteins in new ways, just because we don’t share all of them with the species in question). Cold temperature is actually a special case here, because it slows down everything and thus reduces the amount of “equivalent normal-temperature time” that has passed. It’s still difficult (and of course none of these are impossible), but I don’t think it’s likely that small-scale gene therapy would be sufficient.
Cancer sounds like not-viable to me :P
I meant not even being viable enough to get cancer.
Would it require gene therapy? Could there not be a more direct method of intervention to achieve the result?
The physical structure of the cells have to change. You also don’t see this sort of behavior in large organisms, so there may be serious engineering challenges with the dehydration mechanisms in large animals. You’re essentially going to need powerful, global, highly specific gene therapy at the bare minimum. It might not be possible without engineering a new organism from scratch.
That’s a fair question. I was assuming that creatures which can survive full dehydration are so different at the cellular level that nothing less than genetic redesign would do the job, but I’m guessing.
People die as the result of very moderate dehydration, so considerable change of some sort would be required.
It’s plausible that if dehydration and revival are possible for people, then the methods wouldn’t be much like what’s evolved—people don’t fly the same way birds do.
I think part of the problem, too, is that animals who can survive full dehydration, or being thoroughly frozen within and without, are small. We don’t often realize just how big humans are, even for land-dwelling tetrapods. We’re very large, very active, and very resource-intensive—certainly there are bigger land animals about today and in our recent past, and very much bigger ones in the fossil record (brachiosaurs, anyone?), but even then we still qualify as megafauna.
The consequences of that size, especially in light of our activity level, are significant. Human physiology is very adapted to dissipate heat well (and our water intake is a big part of that), yet we still routinely have trouble doing it fast enough to avoid ill effects, forcing us to adapt culturally and individually to the problem. We have to conserve quantities (of temperature regulation, of water) at fairly specific levels; our physiology is critically dependent on them.
So, yeah—if people can be put in suspended animation of some sort (regardless of mechanism), it’s gonna have to take our particular case into account. You can flash-freeze a mouse, thaw it, and get biological activity after (they don’t exactly go on to live long and prosperous mousey lives, but they do come out the other side for a bit). A mouse is tiny; you can’t extend that to a human without different physics becoming relevant. You can dehydrate a tardigrade quickly (just let it do its thing in a low-moisture environment for long enough until it loses enough water) and then leave it sitting until it gets doused again; you can’t do that to a human, because we have a lot of water to lose, our bodies fight to hang on to it, our health declines rapidly as we lose even modest amounts, and we proceed straight to death once quantities are insufficient.