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Comment by koeng | Hacker News Reader

First approximation - 50 base pairs of RNA? (Unless I am reading the supplement wrong)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3943892/

"The present study describes the directed evolution of replicating RNA enzymes that operate with an exponential growth rate of 0.14 min−1, corresponding to a doubling time of 5 min. Each parental enzyme can give rise to thousands of copies per hour, and each of these copies in turn can do the same, all the while transmitting molecular information across the generations."

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Thanks for that link! That's amazing. I had no idea that work had ever been done.

According to my math 10 million moles of random sequence 50-base pair RNA segments would be required to ensure a correct 'Hit' on a replicator, assuming only one of those 50-long sequences can replicate. 4^50=10^30. 10^30/Avogadro=10^7. Assuming each enzyme is the size of a water molecule, that would be about one large swimming pool of water.

https://nebiocalculator.neb.com/#!/ssrnaamt 10 million moles of RNA of length 50 turns out to be a large amount of RNA... but then again there was like a billion years for life to develop, all around the world.

All around every world in the universe. If life had emerged on planet 5 around star 1778465 in galaxy M33 instead of earth, then people on that planet would be having the same thoughts.

This makes the assumption that all the RNA molecules of 50 bp length are "clean" chains of nucleotides, without any chemical modifications that break the replication process. This is highly unlikely if the RNA is not produced by existing enzymes, but by more or less random chemical processes.

It's purely the math probabilities I was getting at above. If you take the number of molecules in a large swimming pool, that is the same number of 50-long RNA molecules it would take to statistically cause at least one RNA to accidentally have any specific pattern of length 50.

In actual evolution this number of RNA molecules can be thought of as 'diluted' across the entire oceans, and not magically sitting in single pond.

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