Additive Genetic Variance

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Related to Additive Genetic Variance: Quantitative genetics, narrow sense heritability

Additive Genetic Variance

Evolutionary biology The ratio of altered genes and alleles to all of the genes that influence a particular trait
See Genetic variation


1. characterized by addition.
2. a substance added to another to improve its appearance, increase its nutritive value, etc. See feed additive.

food additive
material added to food; includes preservatives, emulsifiers, stabilizers, acids, nonstick agents, humectants, firming agents, antifoaming agents, colorings and flavorings, solvents, and even nutritive materials such as minerals and vitamins.
additive gene action
1. total contribution made by all loci to a polygenic trait.
2. when the heterozygote is intermediate in phenotype between the two homozygotes, i.e. a lack of dominance.
additive genetic relationship
the degree of relationship (number of genes held in common) between two individuals neither of which is inbred; the minimum relationship is 0 and the maximum is 1.0.
additive genetic variance
variance attributed to the mean effect of substituting one allele for another at any given loci.
intramammary infusion additive
agents, e.g. anti-inflammatories, added to improve pharmacological efficacy.
additive relationship
see additive genetic relationship (above).


one of the measures of the dispersion of data; the mean squared deviation of a set of values from the mean.

additive genetic variance
that portion of phenotypic variance which is due to the additive effect of genes (VA).
analysis of variance
a statistical method for comparing values, expressed in terms of means or variance, of one or more variables in several subgroups of a population. Called also anova.
non-additive genetic variance
that portion of phenotypic variance which is due to epistatic interactions (VI) and dominance deviations (VD).
non-genetic variance
that portion of phenotypic variance which is due to non-genetic effects such as environment (VE).
phenotypic variance
a measure of the extent to which individuals vary in their phenotype (VP). VP = VA + VD + VI + VE.
variance ratio distribution
References in periodicals archive ?
8% of the variance--the additive genetic variance and the dominance.
Species-wide differences between male and female intensities of selection and additive genetic variances were tested using this same procedure.
Table 2--Heritability estimates [+ or -] standard errors, first principal component coefficient (FPCC), and the percentage of the direct additive genetic variance (%var) explained by the principal components for all tested models at 100 (W100), 205 (W205), 365 (W365).
m]), path coefficient 3, representing the square root of the proportion of the total phenotypic variance [Mathematical Expression Omitted] determined by the maternal additive genetic variance [Mathematical Expression Omitted]; (2) the maternal environmental variance [Mathematical Expression Omitted] as a fraction of the total phenotypic variance [Mathematical Expression Omitted], path coefficient 4; (3) direct-maternal additive genetic covariance ([[Sigma].
High rates of additive genetic variances ratio and high rates of hereditability for morphometric traits in females demonstrate decrease in the participation of environmental effects within total variation.
If the additive genetic variance in a large population is VA, the expected genetic variance of a purely additive trait in a small population is (1 - 1/2N)[V.
Two hypotheses have been proposed to explain how the additive genetic variance of traits might be affected (Hoffmann and Parsons 1991).
2]) was defined as the ratio of additive genetic variance to phenotypic variance ([h.
Unfortunately, both papers reported heritability estimates that were biased upward because of confounding of the additive genetic variance with dominance variance.
It is directly proportional to the additive genetic variance and is higher in traits governed additively and lower in non-additively controlled traits.
e]; where A = relationship matrix, I = identity matrix, R = residual variance and covariance matrix, = direct additive genetic variance component, [[sigma].