• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of geneticsGeneticsCurrent IssueInformation for AuthorsEditorial BoardSubscribeSubmit a Manuscript
Genetics. Mar 2002; 160(3): 1191–1202.
PMCID: PMC1462034

Selection, load and inbreeding depression in a large metapopulation.


The subdivision of a species into local populations causes its response to selection to change, even if selection is uniform across space. Population structure increases the frequency of homozygotes and therefore makes selection on homozygous effects more effective. However, population subdivision can increase the probability of competition among relatives, which may reduce the efficacy of selection. As a result, the response to selection can be either increased or decreased in a subdivided population relative to an undivided one, depending on the dominance coefficient F(ST) and whether selection is hard or soft. Realistic levels of population structure tend to reduce the mean frequency of deleterious alleles. The mutation load tends to be decreased in a subdivided population for recessive alleles, as does the expected inbreeding depression. The magnitude of the effects of population subdivision tends to be greatest in species with hard selection rather than soft selection. Population structure can play an important role in determining the mean fitness of populations at equilibrium between mutation and selection.

Full Text

The Full Text of this article is available as a PDF (143K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Felsenstein J. The theoretical population genetics of variable selection and migration. Annu Rev Genet. 1976;10:253–280. [PubMed]
  • Fowler K, Whitlock MC. The variance in inbreeding depression and the recovery of fitness in bottlenecked populations. Proc Biol Sci. 1999 Oct 22;266(1433):2061–2066. [PMC free article] [PubMed]
  • García-Dorado A, Caballero A. On the average coefficient of dominance of deleterious spontaneous mutations. Genetics. 2000 Aug;155(4):1991–2001. [PMC free article] [PubMed]
  • García-Dorado A, López-Fanjul C, Caballero A. Properties of spontaneous mutations affecting quantitative traits. Genet Res. 1999 Dec;74(3):341–350. [PubMed]
  • Houle D, Hughes KA, Assimacopoulos S, Charlesworth B. The effects of spontaneous mutation on quantitative traits. II. Dominance of mutations with effects on life-history traits. Genet Res. 1997 Aug;70(1):27–34. [PubMed]
  • Hughes KA. The inbreeding decline and average dominance of genes affecting male life-history characters in Drosophila melanogaster. Genet Res. 1995 Feb;65(1):41–52. [PubMed]
  • Kimura M, Maruyama T. The mutational load with epistatic gene interactions in fitness. Genetics. 1966 Dec;54(6):1337–1351. [PMC free article] [PubMed]
  • Kimura M, Weiss GH. The Stepping Stone Model of Population Structure and the Decrease of Genetic Correlation with Distance. Genetics. 1964 Apr;49(4):561–576. [PMC free article] [PubMed]
  • Kirkpatrick M, Jarne P. The Effects of a Bottleneck on Inbreeding Depression and the Genetic Load. Am Nat. 2000 Feb;155(2):154–167. [PubMed]
  • Kondrashov AS, Crow JF. King's formula for the mutation load with epistasis. Genetics. 1988 Nov;120(3):853–856. [PMC free article] [PubMed]
  • Bataillon T, Kirkpatrick M. Inbreeding depression due to mildly deleterious mutations in finite populations: size does matter. Genet Res. 2000 Feb;75(1):75–81. [PubMed]
  • Rasmussen LK, Due HA, Petersen TE. Human alpha s1-casein: purification and characterization. Comp Biochem Physiol B Biochem Mol Biol. 1995 May;111(1):75–81. [PubMed]
  • Ota T, Cockerham CC. Detrimental genes with partial selfing and effects on a neutral locus. Genet Res. 1974 Apr;23(2):191–200. [PubMed]
  • Otto SP, Orive ME. Evolutionary consequences of mutation and selection within an individual. Genetics. 1995 Nov;141(3):1173–1187. [PMC free article] [PubMed]
  • Caballero A, Hill WG. Effects of partial inbreeding on fixation rates and variation of mutant genes. Genetics. 1992 Jun;131(2):493–507. [PMC free article] [PubMed]
  • Pollak E. Some effects of selection when there is partial full-sib mating. Genetics. 1995 Jan;139(1):439–444. [PMC free article] [PubMed]
  • Pollak E, Sabran M. On the theory of partially inbreeding finite populations. III. Fixation probabilities under partial selfing when heterozygotes are intermediate in viability. Genetics. 1992 Aug;131(4):979–985. [PMC free article] [PubMed]
  • Robertson A. The Effect of Inbreeding on the Variation Due to Recessive Genes. Genetics. 1952 Mar;37(2):189–207. [PMC free article] [PubMed]
  • Cockerham CC. Higher order probability functions of identity of allelles by descent. Genetics. 1971 Oct;69(2):235–246. [PMC free article] [PubMed]
  • Tachida H, Cockerham CC. Quantitative genetic variation in an ecological setting. Theor Popul Biol. 1987 Dec;32(3):393–429. [PubMed]
  • Tachida H, Cockerham CC. A building block model for quantitative genetics. Genetics. 1989 Apr;121(4):839–844. [PMC free article] [PubMed]
  • Wang J. Effects of population structures and selection strategies on the purging of inbreeding depression due to deleterious mutations. Genet Res. 2000 Aug;76(1):75–86. [PubMed]
  • Wang J, Hill WG, Charlesworth D, Charlesworth B. Dynamics of inbreeding depression due to deleterious mutations in small populations: mutation parameters and inbreeding rate. Genet Res. 1999 Oct;74(2):165–178. [PubMed]
  • Eyre-Walker A, Keightley PD. High genomic deleterious mutation rates in hominids. Nature. 1999 Jan 28;397(6717):344–347. [PubMed]
  • Whitlock MC. Fixation of new alleles and the extinction of small populations: drift load, beneficial alleles, and sexual selection. Evolution. 2000 Dec;54(6):1855–1861. [PubMed]
  • Whitlock MC, McCauley DE. Indirect measures of gene flow and migration: FST not equal to 1/(4Nm + 1). Heredity (Edinb) 1999 Feb;82(Pt 2):117–125. [PubMed]
  • Wright S. Evolution in Mendelian Populations. Genetics. 1931 Mar;16(2):97–159. [PMC free article] [PubMed]
  • Wright S. The Distribution of Gene Frequencies in Populations. Proc Natl Acad Sci U S A. 1937 Jun;23(6):307–320. [PMC free article] [PubMed]

Articles from Genetics are provided here courtesy of Genetics Society of America


Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


  • MedGen
    Related information in MedGen
  • PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...