Backward evolution from gene network dynamics

Gene expression is often controlled by regulator genes that form gene regulatory network cascades. How mutation in the genes comprising regulatory cascades influences cell populations dynamics has not been adequately investigated. In this study, we developed a model to study how a mutation in a regulator gene that reaches the effector gene with a time delay affects short-term and long-term population growth. We find a paradoxical outcome of evolution, where a mutation in a regulator gene leads to an interaction between gene regulatory network dynamics and population dynamics, causing in certain cases a permanent decrease in population fitness.