Abstract
Genetic diversity of viral populations is almost unanimously attributed to the build-up of random mutations along with accidental recombination events. This passive role of viruses in the selection of viable genotypes is widely acknowledged. According to the hypothesis presented here, populations of steady-state error copies of a master viral sequence would have a dominant mutant rather than a random pool of heterogeneous viral genomes with changes scattered uniformly without any preferential distribution. It would let viruses face the selection stage of host surveillance having a preceding set of potential survivors or "guard" genomes among an ordinary cloud of random quasispecies.