Escape from Eigen's paradox for prebiotic genomes · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Escape from Eigen's paradox for prebiotic genomes
Plain
Copying without enzymes is sloppy, so only short sequences survive copying errors, yet an accurate copying enzyme needs a sequence long enough to encode it. A 2026 RNA enzyme only 45 letters long narrowed this gap, and which mechanism kept genetic information intact over many generations is still open.
Precise · changed · core
Revision 1: With nonenzymatic copying fidelity $q \sim 0.9\ \text{to}\ 0.99$ per nucleotide, $L_{\mathrm{max}} \sim \operatorname{ln}(\sigma)/(1 - q)$ is tens to about a hundred nucleotides; polymerase ribozymes derived from the class I ligase are about 200 nucleotides long, while the 45-nucleotide QT45 ribozyme (Science 2026) copies at $q = 0.941$, giving $L_{\mathrm{max}} \sim 17 \operatorname{ln}(\sigma)$. Find a mechanism (compartments with group selection, hypercycles, template-directed ligation of short oligomers, spatial structure on surfaces) that maintains information content exceeding $L_{\mathrm{max}}$ over many replication rounds, stable against parasitic sequences, for a replicase that copies itself from mononucleotides or mixed-length feedstocks, with parameters measured in prebiotic chemistry.
Revision 2: With nonenzymatic copying fidelity $q \sim 0.9\ \text{to}\ 0.99$ per nucleotide, $L_{\max} \sim \ln(\sigma)/(1 - q)$ is tens to about a hundred nucleotides; polymerase ribozymes derived from the class I ligase are about 200 nucleotides long, while the 45-nucleotide QT45 ribozyme (Science 2026) copies at $q = 0.941$, giving $L_{\max} \sim 17 \ln(\sigma)$. Find a mechanism (compartments with group selection, hypercycles, template-directed ligation of short oligomers, spatial structure on surfaces) that maintains information content exceeding $L_{\max}$ over many replication rounds, stable against parasitic sequences, for a replicase that copies itself from mononucleotides or mixed-length feedstocks, with parameters measured in prebiotic chemistry.
Settled by · changed · core
Revision 1: A quantitative model with experimentally measured copying, ligation and compartment-division rates showing maintained information above $L_{\mathrm{max}}$, ideally confirmed in an experiment.
Revision 2: A quantitative model with experimentally measured copying, ligation and compartment-division rates showing maintained information above $L_{\max}$, ideally confirmed in an experiment.
Kind
well-posed
Answer type
mechanism
References
(empty)
Literature status
partially-resolved
Status note
A 45-nucleotide polymerase ribozyme (2026) brought the replicator size close to the error threshold; maintenance against parasites over many rounds has not been demonstrated.
Posed since
1971

Decisions