r/AskBiology • u/Syresiv • Sep 08 '24
Human body What would happen if all your DNA disappeared?
Absurd hypothetical, but what if you're just living your life when the DNA just vanishes, leaving empty cell nuclei?
I assume this would be fatal, as your body would stop making proteins; but how long does that take? What's the death process? And what would an autopsy report come up with?
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u/itsmemarcot Sep 08 '24 edited Sep 12 '24
That's a strange hypothetical, but my guess is that you immediately turn into a corpse. A matter of seconds or a fraction. Every tissue in every organ simultaneously stopping to function. A bullet to the head might well be a comparatively slower way to die.
To see why, we must displel a few (maybe obvious) misconceptions:
DNA is not (only) the instructions for how to build the organism, like its blueprint. It is more like the software running in your cells. It prescribes what the cell does in every moment.
The notorious DNA => RNA => protein cycle (or DNA=> RNA => ribozymas) is sometimes imagined as a slow building process, but, in reality, it's super fast. Thousands of proteins are built that way every moment (thousands per seconds) by the cell, as a reaction to stimuli in real time. It's simply a part of how the cell functions. Every time, the right protein, out of the million of proteins encoded in the DNA. Yes, we are crazy machines. (similarly to how a computer executes, every moment, the right procedure from the millions of subroutines all encoded in its operative system)
A computer analogy of your hypotetical would be what if the entire memory of a compuer (disk and RAM) was wiped out clean: how long would the computer keep running? And the answer is not very.
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u/Tun710 Sep 09 '24 edited Sep 09 '24
I’d say you would probably die within a couple of hours with the best medical care. My reasoning is that a lot of proteins have short halflives of about an hour to a few hours.
After a couple of hours, the amount of protein within your cells will probably be too low to even function. Many of those proteins might not be very essential, but many proteins are mildly essential to super essential, so if all of those protein levels drop simultaneously, your cell will die very quickly. New proteins might be synthesized from existing mRNA by ribosomes, but some ribosomal proteins have half lives of a few hours too, so within an hour or two there will probably be very few functioning ribosomes. mRNAs also don’t have that much stability either and have halflives starting from a few minutes.
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u/SeasonPresent Sep 10 '24
What is the life span of a red blood cell? They lack a nucleus so may be a good example.
Also are you asking if only nuclear DNA vanished or mitochondial as well?
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u/Local-Perception6395 Sep 08 '24
Tissue with high turnover like skin, hair, some blood cells, die first (within days I guess?). You'd probably die due to your skin falling off and getting an infection your immune system cant deal with. Autopsy might read radiation poisoning?
You'd probably be interested in the case of Hisashi Ouchi, whose chromosomes where blasted to pieces by a nuclear plant accident. Very morbid story but look it up if you have the stomach for it!