  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.
