Gene flow
![Gene flow is the transfer of alleles from one population to another population through immigration of individuals. In this example, one of the birds from population A immigrates to population B, which has fewer of the dominant alleles, and through mating incorporates its alleles into the other population.](/Images/godic/202501/15/Gene_flow_final5346.png")
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In population genetics, gene flow (also known as gene migration) is the transfer of alleles or genes from one population to another.
Migration into or out of a population may be responsible for a marked change in allele frequencies (the proportion of members carrying a particular variant of a gene). Immigration may also result in the addition of new genetic variants to the established gene pool of a particular species or population.