overdominance


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Related to overdominance: Multiple alleles

o·ver·dom·i·nance

(ō'vĕr-dom'i-năns),
That state in which the heterozygote has greater phenotype value and perhaps is more fit than the homozygous state for either of the alleles that it comprises. Compare: balanced polymorphism.

overdominance

(ō′vər-dŏm′ə-nəns)
n.
The condition of a heterozygote having a phenotype that is more pronounced or better adapted than that of either homozygote.

o′ver·dom′i·nant adj.

o·ver·dom·i·nance

(ō'vĕr-dom'i-năns)
That state in which the heterozygote has greater phenotype value and perhaps is more fit than the homozygous state for either of the alleles that it comprises.
Compare: balanced polymorphism

overdominance

a phenotypic condition in which the HETEROZYGOTE expresses a stronger manifestation of the trait than either HOMOZYGOTE. Overdominance produces heterozygous advantage that can maintain a GENETIC POLYMORPHISM in a population.
References in periodicals archive ?
Being greater or lesser than 1 show the relative dominance and overdominance of genes.
It is pertinent to mention that this overdominance can be of false type and due to gamete disequilibrium.
And again, we investigate relatively simple configurations in which the advantageous allele's importance is proportional to its presence for the case of dominance and in which the heterozygote is maximally advantaged in the case of overdominance.
Similarly, the difference in relative fitness between dominance and overdominance in which the heterozygote is relatively advantaged or disadvantaged, although profound, did not vary the overall trend, although it substantively constrained the range of outcomes.
It must be noted that detection of imprinting effects, including polar overdominance, requires segregation of marker alleles within the lines that are crossed, and is not possible in inbred line crosses.
Many Mendelian QTL with complete or overdominance mode of gene action were detected in this study.
Inbreeding and overdominance as evidenced by biochemical polymorphism in a wild population.
In a previously study, the segregation of an autosomal major gene with overdominance inheritance affecting litter size has been found in Baluchi sheep using Gibbs sampling approach with a mixed major gene-polygenic model (Saneei and Nejati-Javaremi, 2000).