DNA energy constraints shape biological evolutionary trajectories

TL;DR

This paper demonstrates that physical properties and energy constraints of double-stranded DNA, rather than evolutionary pressures alone, significantly influence DNA sequence patterns and symmetries, highlighting the role of physics in biological evolution.

Contribution

It reveals that DNA sequence symmetries and biases can arise from physical and entropy considerations, challenging the view that evolution solely shapes genetic information.

Findings

DNA symmetries emerge from physical properties and entropy principles.

Physical constraints influence DNA sequence architecture more than selective pressures.

Randomness explains codon biases and mutation patterns in human genomes.

Abstract

Most living systems rely on double-stranded DNA (dsDNA) to store their genetic information and perpetuate themselves. This biological information has been considered the main target of evolution. However, here we show that symmetries and patterns in the dsDNA sequence can emerge from the physical peculiarities of the dsDNA molecule itself and the maximum entropy principle alone, rather than from biological or environmental evolutionary pressure. The randomness justifies the human codon biases and context-dependent mutation patterns in human populations. Thus, the DNA "exceptional symmetries", emerged from the randomness, have to be taken into account when looking for the DNA encoded information. Our results suggest that the double helix energy constraints and, more generally, the physical properties of the dsDNA are the hard drivers of the overall DNA sequence architecture, whereas the biological selective processes act as soft drivers, which only under extraordinary circumstances overtake the overall entropy content of the genome.