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Radiation is the ultimate bane of all organic life. Its particles punch holes in our DNA, causing mutations and giving us cancer. But, is there a way to make an organism that is unable to get radiation poisoning?

I don't want it to have something like the Tardigrade's tun, in which it dehydrates itself and becomes immortal, or some kind of lead scales that block the radiation.

I mean that the organism itself has some kind of natural process or characteristic that resists the effects of radiation entirely. As in, if a chunk of uranium was shoved inside its body, it would suffer no ailments whatsoever (aside from the ailments one would expect from having a large foreign object lodged in your flesh).

It wouldn't have to be an evolved trait, the creature in question could be a genetically modified organism.

Is this possible, or does radiation and life simply not mix?

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    $\begingroup$ We can't make it "completely immune", because strong enough radiation will simply fry it. What we can is to make it "highly tolerant". $\endgroup$ – Alexander Jan 9 at 23:02
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    $\begingroup$ Deinococcus radiodurans... It appears that its fantastic ability to shrug off doses of radiation which would kill dead any other bacteria (and of course all higher lifeforms) is somehow linked to its ability to resist dessication; that is, the mechanisms which repair DNA broken by prolonged dessication. It was discovered when scientists, while developing the process of sterilizing canned food by exposing it to gamma radiation, noticed it growing happily that after taking a dose supposed theoretically to kill all known life-forms. $\endgroup$ – AlexP Jan 9 at 23:13
  • $\begingroup$ i remember about certain worm that can heal from radiation poisoning by getting implant from healthy worm parts is that ok ? i dont know the science explanation though. $\endgroup$ – Li Jun Jan 10 at 1:05
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    $\begingroup$ @AlexP: sorry but Thermococcus gammatolerans just dethroned yours ;P $\endgroup$ – user6760 Jan 10 at 1:15
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    $\begingroup$ There are some fungi that can actually get energy from radiation:en.wikipedia.org/wiki/Radiotrophic_fungus. Maybe your organism could do something similar? $\endgroup$ – alexgbelov Jan 10 at 23:54
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Your organism could do one or more of the things computer scientists do when they want to ensure data doesn't get corrupted.

First, include a checksum in your DNA. Checksums involve adding up all the individual bits of a piece of data and comparing the result to what it should be. If the two numbers aren't the same, you know either the checksum has been damaged or the data has been damaged. Either way, you can't trust the data.

Second, use RAID storage. This involves having 3 or more copies of your data. You can tell one copy has been damaged because it disagrees with the others. Then you can use the undamaged copies to repair or replace the damaged copy.

These both are very effective at detecting errors in electronic data, and so should work fine in DNA as well. But they do have some drawbacks.

First, checksums can have false positives. If the checksum has been damaged, it'll look just like the data has been damaged. So the DNA may actually be fine, but the cell will still look cancerous. I think this is OK, it's probably better to err on the side of caution, but it's still an inefficiency.

Second, RAID storage requires several copies of your data, which most of the time are just dead weight.

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    $\begingroup$ Checksums can also give false negatives - there are multiple data sequences that match a given checksum. But it would improve resilience to radiation. $\endgroup$ – Paul92 Jan 10 at 9:14
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Radiation and Life Don't Mix

Essentially, when you get down to it, radioactive matter is just unstable matter which makes the matter around it unstable. It's like trying to build a large and complex tower of blocks, except some blocks are radioactive and thus will randomly explode.

Radiation attack molecular life at the atomic level, and there's not really a perfect defense against that. What you can do is have redundant systems - extra copies of all the necessary proteins, multiple independent DNA storage sites, incredibly fast and accurate repair enzymes. Going back to out tower of blocks, you basically decide that you're going to just build as wide as you can, and ignore height so even when some blocks explode, no individual block is actually necessary to keep that tower up.

What you end up with is something that's designed to not die from radiation. It doesn't resist the radiation so much as have the capacity to repair itself no matter the damage. It will still die if you hit it with enough radiation, after all, any block tower can be blown to smithereens with enough exploding blocks. It will also be very small and simple, possibly not even more complex than a single strain of bacteria, but it will resist radiation entirely.

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  • $\begingroup$ On the contrary, life (other than a bit of chemosynthetic stuff in e.g. undersea vent communities) depends on solar radiation. And to some extent it depends on ionizing radiation as well, as that is one of the things that cause mutations, and thus allow evolution. The problem, as with anything, is excess. A daisy happily photosynthesizing in the sunlight would be in dire trouble if hit with a multi-megawatt laser beam. $\endgroup$ – jamesqf Jan 10 at 5:08
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DNA Horcrux

In the Harry Potter books, Lord Voldemort stored his soul in a horcrux, making him unkillable. The horcrux(es) were kept safely off site. A radiation impervious organism could keep its DNA outside of its body, in a safe place.

Strong enough radiation will kill via thermal energy denaturing proteins: this is "cooking". But lesser doses of ionizing radiation kill or mutate by disrupting DNA.

There are cells in the body which jettison their DNA after development. Red blood cells do not have DNA. Other cells which are liable to have DNA damaged because they are exposed to the environment (for example skin cells) have finite lifespans so damaged DNA cannot turn into cancer within the lifespan of the cell.

Your impervious organism would have no DNA in any cell and would be immune to cancer. I envision this organism as like a worker ant. It would visit its DNA Horcrux (perhaps a queen of some sort) and receive an infusion of fresh stem cells. These cells would move through the organism, replicating in there and repairing/ renewing organs. The new cells use the scaffolds of the old as templates. The cells build up stores of RNA. During this time the organism could be hurt by radiation, but it is hiding in the hive.

Once that is done, all cells eject their nuclei - possibly into some place in the hive where the queen can eat them. The organism sallies out with no DNA on board. It will need to return for new stem cells periodically, but it is good for several weeks.

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    $\begingroup$ I like the concept, but cells don't live that long. The Destroying Angel mushroom terminates DNA reproduction and causes death within two days. Red blood cells are incredibly specialized, and don't have high-stress positions, but cells forming the muscles, bone, and gut are going to deteriorate in a few days without the ability to build more proteins. $\endgroup$ – Halfthawed Jan 10 at 0:11
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    $\begingroup$ Destroying Angel mushroom blocks production of RNA from DNA and by doing so prevents protein synthesis from RNA. Cells need a steady supply of proteins. By laying in supplies of RNA in advance, the cells of this creature avoid this problem and dance a merry jig atop a heap of Destroying Angel mushrooms. $\endgroup$ – Willk Jan 10 at 0:58
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    $\begingroup$ And the RNA stores won't get denatured from the radiation? $\endgroup$ – Halfthawed Jan 10 at 0:58
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    $\begingroup$ @Halfthawed - sure they will. But a protein with a few wrong amino acids has a fighting chance of functioning, and no chance of triggering some dormant fetal growth program like mutant DNA might. $\endgroup$ – Willk Jan 10 at 1:40

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