Fig. 1: A schematic demonstrating how function is lost in an engineered population over evolutionary time.
From: Genetic controllers for enhancing the evolutionary longevity of synthetic gene circuits in bacteria
Random mutations occur as a result of error-prone DNA replication, leading to mutants with reduced circuit function. These mutants have higher selective fitness, as the host cells can direct more resources towards growth. As a result, such mutants dominate the population and circuit function is eventually lost.
