title: A fundamental relationship between genotype frequencies and fitnesses.
abstract: The set of possible postselection genotype frequencies in an infinite, randomly mating population is found. Geometric mean heterozygote frequency divided by geometric mean homozygote frequency equals two times the geometric mean heterozygote fitness divided by geometric mean homozygote fitness. The ratio of genotype frequencies provides a measure of genetic variation that is independent of allele frequencies. When this ratio does not equal two, either selection or population structure is present. Within-population HapMap data show population-specific patterns, while pooled data show an excess of homozygotes.
authors.affiliation: Department of Ecology and Evolution, State University of New York, Stony Brook, New York 11794-5222, USA. joseph.lachance@sunysb.edu
authors.forename: Joseph
authors.initials: J
authors.lastname: Lachance
mesh_terms: D005787:Gene Frequency / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D008957:Models, Genetic; D010641:Phenotype
references.citation: Hum Mol Genet. 2004 Mar 15;13(6):577-88
references.pmid: 14734624
references.citation: Trends Ecol Evol. 1996 May;11(5):201-6
references.pmid: 21237809
references.citation: Evolution. 2008 Feb;62(2):255-65
references.pmid: 18302709
references.citation: J Mol Biol. 1963 Jul;7:95-9
references.pmid: 13990617
references.citation: Genet Res (Camb). 2008 Apr;90(2):209-16
references.pmid: 18426624
references.citation: Genetics. 2007 Jul;176(3):1625-33
references.pmid: 17483422
references.citation: Genetics. 2005 Dec;171(4):1741-56
references.pmid: 16143618
references.citation: Genetics. 1978 Jan;88(1):149-69
references.pmid: 17248790
references.citation: Theor Popul Biol. 1989 Oct;36(2):167-80
references.pmid: 2814903
references.citation: Biometrics. 1989 Mar;45(1):53-70
references.pmid: 2720060
references.citation: Genetics. 1985 Nov;111(3):655-74
references.pmid: 3932127
references.citation: Nature. 2003 Dec 18;426(6968):789-96
references.pmid: 14685227
references.citation: Ann Hum Genet. 1968 May;31(4):421-8
references.pmid: 5673165
references.citation: Proc R Soc Lond B Biol Sci. 1953 Sep;141(905):510-23
references.pmid: 13100409