> Not enough to scan brain connectivity info, neuron types and per-person genome, you will now also need per-neuron genomes to truly capture and reproduce a brain.

Is the cup half-full or half-empty? From one perspective, if the known fixed functionality of the brain is implemented in part using DNA mutations, this is good long-term news - after all, if there is one thing you can expect to be kept intact and be recoverable in a vitrified brain, it's the DNA. That makes decoding more difficult, but also makes information-theoretic death less likely.

If these mutations are random they can probably be ignored. They likely have no effect or negative effects. Your brain might actually improve a lot by removing them.

If they aren't random and there is some purpose or information encoded in them, then you have a good point. I think that's unlikely though.

Clearly you haven't worked on an old buggy codebase. Sure that function has a bug, but the rest of the codebase has adapted to it and worked around it. If the function suddenly doesn't have a bug, dozens of other functions will fail in new and strange ways.

The brain would work in a very similar way. If a neuron has a mutation that effects it's function, surrounding neurons would adapt to that.

Having worked in such codebases, the only difference that should be happening is that a lot of that old, redundant code inserted to work around the bug would no longer be visited.

It is extremely unlikely that the brain encodes information by introducing controlled mutations into DNA. Random mutations would add noise, not information.

It is likely that some mutations affect the efficiency of signal propagation, and encoding might adapt to this, so that equivalent inputs would create more or fewer or "stronger" or "weaker" synapses to generate the same output from the second neuron. But this could be detected functionally, if you could observe the signals and responses of neuron pairs.

Our immune system is also full of somatic hyper-mutated cells.