Imperfect DNA Repair and the Error Catastrophe

In this Letter, we extend the semiconservative quasispecies equations to incorporate imperfect DNA lesion repair. We study the equilibrium behavior of this model in the limit of infinite sequence length and population size, using a single-fitness-peak landscape for which the master genome can sustain a finite number of lesions and remain viable. We provide a full analytical treatment of the problem, providing a general mathematical framework as well as the full solution for a particular class of fitness landscapes. Stochastic simulations using finite sequence lengths and populations agree well with the analytical results. Applications to biological systems are briefly discussed.