title: Epistasis and its contribution to genetic variance components.
abstract: We present a new parameterization of physiological epistasis that allows the measurement of epistasis separate from its effects on the interaction (epistatic) genetic variance component. Epistasis is the deviation of two-locus genotypic values from the sum of the contributing single-locus genotypic values. This parameterization leads to statistical tests for epistasis given estimates of two-locus genotypic values such as can be obtained from quantitative trait locus studies. The contributions of epistasis to the additive, dominance and interaction genetic variances are specified. Epistasis can make substantial contributions to each of these variance components. This parameterization of epistasis allows general consideration of the role of epistasis in evolution by defining its contribution to the additive genetic variance.
authors.affiliation: Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Cheverud
authors.forename: E J
authors.initials: EJ
authors.lastname: Routman
mesh_terms: D000818:Animals; D001835:Body Weight / Q000235:genetics; D004843:Epistasis, Genetic; D005819:Genetic Markers / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D051379:Mice
chemical_list: D005819:Genetic Markers