Monte Carlo simulation of genome viability with paralog replacement.

Recent analyses of genome content have revealed that many single functions, even in haploid organisms, can be executed by more than one gene. As a result, experimental disruption of many individual genes does not exert lethal effects on the organism or even any visible change in the phenotype of the organism with a knockedout gene. Our analysis shows that such genetic redundancy allows for an appreciably higher mutation load in the genome simulations before the viability of the whole organism is destroyed.