Nonenzymatic DNA Polymerization in Prebiotic Protocell Models: A Theoretical Analysis

The origin of DNA in prebiotic environments remains a central question in molecular evolution. While RNA-first hypotheses dominate, theoretical and experimental studies suggest that DNA may form abiotically under mineral-assisted conditions. Here, we present a fully analytical framework demonstrating direct DNA production via nonenzymatic polymerization within protocell-like environments. Using literature-based kinetic constants, mineral enhancement factors, and realistic wet-dry cycling conditions, we show that DNA monomers and oligomers can accumulate preferentially over RNA. Our model predicts DNA oligomer yields of 6–7% within 48 hours, comprising ~96% of total polymer content, confirming that prebiotic DNA synthesis is feasible under realistic early Earth conditions.