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Related to overdominance: Multiple alleles


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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


excessive dominance
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Swamp Rats eat the rhizomes of sedges with the potential for overdominance such as Sandhill Swordsedge and Thatch Saw-sedge (author, pers.
A quantitative trait locus genome scan for porcine muscle fiber traits reveals overdominance and epistasis.
Theoretically, heterosis, also called hybrid vigour, can be expressed indirectly through higher horn growth rates, presumably due to increased heterozygosity for loci with overdominance (Lippman and Zamir 2006, Keller and Taylor 2010).
It has enjoyed sufficient oak exposure to provide smoothness and a butterscotch background without overdominance. Gentle, but zesty, tangerine based acidity sets off the wine's soft, pineapple, apricot and pear fruit beautifully.
In goats, it was reported that the INHA 651A/G polymorphism was a potential marker for the mean litter size of the second parity in Boer goats, which showed an overdominance effect (Wu et al., 2009).
Genetic studies on the Pacific abalone-I inbreeding and overdominance as evidenced by biochemical polymorphism in a wild population.
High heterozygosity of successful rampant clones may indicate the effect of overdominance, and the studied "Meshabash" clone is a good example of heterozygote superiority.
Based on single and two-locus QTL analysis, dominance [10], overdominance [3, 14, 15, 18, 19], epistasis [2, 16, 20], and accumulated effects [8, 12, 21-25] could be the major determinants of heterosis in rice.
The average degree of dominance as indicated by the ratio [([H.sub.1]/D).sup.1/2] suggested overdominance of this trait in both environments.
Inbreeding depression results from the expression of deleterious recessive alleles or from overdominance (Charnov, 1982; Charlesworth and Willis, 2009).
From shiny boardrooms to miners' informal shack housing, the economy's overdominance by finance is leading to economic choices that increase inequality and undermine long-term social and economic stability.