overdominance


Also found in: Dictionary, Medical, Wikipedia.
Related to overdominance: Multiple alleles

overdominance

[¦ō·vər′däm·ə·nəns]
(genetics)
Monohybrid heterosis, that is, the phenotype is being more pronounced in the heterozygote than in either homozygote with respect to a specified pair of alleles.
Mentioned in ?
References in periodicals archive ?
1991) studied the quantitative traits in bread wheat using graphic analysis, and showed that genes control the traits plant height and spike length by incomplete dominance, weight of 1000 seeds by complete dominance, number of seeds per spike, number of spikelet per spike, and seed weight per spike by overdominance.
For overdominance, the animal heterozygous at all designated loci has AdultFitness = 1, and animals homozygous at all designated loci have AdultFitness = O.
The feature was the result of expression of a normal copy of a specific gene from the mother and a mutated copy of the same gene from the father--an inheritance pattern known as paternal polar overdominance.
Hitchhiking and associative overdominance at a microsatellite locus.
A specific mode of genomic imprinting that has been uncovered in mammals is polar overdominance (POD), for which one type of heterozygous progeny differs in phenotype from the other heterozygous type, depending on the parent from which the mutant allele was received, and also differs from the two types of homozygotes.
Three hypotheses of nonadditive gene action may explain heterosis: overdominance (Shull 1908, East 1936), dominance (Bruce 1910) and epistasis (Stuber et al.
Assertiveness can spill into overdominance, overcontrolling and even bullying behaviour.
Identification of the single base change causing the callipyge muscle hypertrophy phenotype, the only known example of polar overdominance in mammals.
Overdominance in early life stages of an American oyster strain.