Genetic Drift in Human Populations


Genetic drift consists of changes in allele frequencies due to sampling error. Even if all individuals in a population have the same opportunities to mate, their reproductive contributions to the next generation will vary due to random chance alone. In any population of finite size, this sampling error will cause gene frequencies to fluctuate from generation to generation. Genetic changes due to drift are neither directional nor predictable in any deterministic way. Nonetheless, genetic drift leads to evolutionary change even in the absence of mutation, natural selection or gene flow.

Keywords: bottleneck; effective population size; heterozygosity; population genetics; neutral theory of evolution


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How to Cite close
Bohonak, Andrew J(Apr 2008) Genetic Drift in Human Populations. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0005440.pub2]