Genetic Equilibrium

Genetic equilibrium describes the condition of an allele or genotype in a gene pool (such as a population) where the frequency does not change from generation to generation. Genetic equilibrium describes a theoretical state that is the basis for determining whether and in what ways populations may deviate from it. Hardy-Weinberg equilibrium is one theoretical framework for studying genetic equilibrium. It is commonly studied using models that take as their assumptions those of Hardy-Weinberg, meaning: • No gene mutations occurring at that locus or the loci associated with the trait • A large population size • Limited-to-no immigration, emigration, or migration (genetic flow) • No natural selection on that locus or trait • Random mating (panmixis) It can describe other types of equilibrium as well, especially in modeling contexts. In particular, many models use a variation of the Hardy-Weinberg principle as their basis. Instead of all of the Hardy-Weinberg characters being present, these instead assume a balance between the diversifying effects of genetic drift and the homogenizing effects of migration between populations. A population not at equilibrium suggests that one of the assumptions of the model in question has been violated.