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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.


excessively dominant
References in periodicals archive ?
Heterosis that is caused by heterozygosity in single loci is responsible for survival rate by increasing reproductive fitness [22], Hayes and Miller (2000) showed that dominance effect was needed in mate selection to exploit previously untapped genetic variation [23], while Dekkers and Chakraborty (2004) stressed maximization of crossbred performance by incorporating information from overdominant QTL [24], Kim et al [8] found that many QTL for growth and carcass quality had a (over) dominant mode of gene action in a cross between Angus and Brahman cattle [8], The use of dominance effects in a scenario of genomic selection increases the accuracy of estimated breeding values and still offers the opportunity of applying mate-allocation.
And in the latest sign that Mr Corbyn's campaign intends to highlight Mr Smith's background as an employee of pharmaceutical giant Pfizer, the Labour leader said at his launch: "I hope that Owen will fully agree with me that our NHS should be free at the point of use, should be run by publicly employed workers, working for the NHS, not for private contractors, and that medical research shouldn't be farmed out to big pharmaceutical companies like Pfizer and others but should be funded through the medical research council as a way of developing those drugs and not allowing the private pharma companies [to] become overdominant in the way the NHS provides [medicine].
They stated that if the heterosis is manifested by the parents with high x high, low x high and low x low general combining ability, it indicated the involvement of additive, additive genes with complementary effects, overdominant and epistasis gene interactions, respectively.
Seedcotton per plant was partial dominant in seven irrigations treatment while it inherited as an overdominant trait in five four and three irrigations respectively.
Nevertheless, the Romanian political scene was unbalanced by the existence of an overdominant political formation, with a political adversary to seriously contest its position (Gilia, 2013: 56).
section]) Genotypic odds ratios (ORs) are shown because these exceed allelic ORs for DDT (recessive model), bendiocarb, and fenitrothion (both overdominant models), and are similar for permethrin and deltamethrin.
To find overdominant genes, the team developed a novel approach by turning to a vast tomato "mutant library" - a collection of 5,000 plants, each of which has a single mutation in a single gene that causes defects in various aspects of tomato growth, such as fruit size and leaf shape.
Growth rate in oysters: an overdominant phenotype and its possible explanations.
Overdominant epistatic loci are the primary genetic basis of inbreeding depression and heterosis in rice.
Indeed, "[T]here is a recurring fear that an overdominant Southern wing will drag the GOP onto the cliffs of extremism in the same way that the McGovernite wing pulled the Democrats too far to the Left during the 1970s.