Codominance

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codominance

[kō′däm·ə·nəns]
(genetics)
A condition in which each allele of a heterozygous pair expresses itself fully, as in human blood group AB individuals.

Codominance

 

expression in heterozygotes of characters typical of both forms (alleles) of the gene.

Codominance is found, for example, in studying blood serum proteins (transferrins). In individuals heterozygous for the alleles controlling the biosynthesis of transferrin, both forms of this protein are present in the blood at the same time, and each form is found separately in the corresponding homozygote. The same patterns of heredity are also found in other proteins, including almost all the enzymes. The degree of activity of each of the allelic genes may be different. The products synthesized under the control of two alleles of the same gene may independently influence the expression of a character or they may interact with each other. The existence of codominance is useful in studying the genetic structure of populations without making crossings or studying pedigrees; instead, modern biochemical and immunological methods of separating proteins are used. Codominance in erythrocytic antigens facilitates the identification of blood groups in man and animals.

V. S. KIRPICHNIKOV

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In addition, the rank reversals that were observed could have resulted from the single losing experience of the dominant (after the previous win), "resetting" the dominant to subordinate status, and thus having two new subordinates re-forming a dominance relationship with equal opportunity for each animal to obtain higher rank.
At the beginning of the first phase (P1; 0-20 min), the divider was removed and the animals were allowed to interact and to establish a dominance relationship.
The control was conducted to see if transferring the animals twice, and temporary separation from the opponent, could alone cause distabilization of the dominance relationship.
To classify settlements take the following steps: 1) determine weights of indices; 2) assign qualifications to all qualitative indices; 3) determine utilities of quantitative indices using equations (1), (2), (3), associating scoring scales to the qualifications of qualitative indices, and fill in the matrix of utilities; 4) compute coefficients of concordance using equation (4) and fill in the matrix of coefficients of concordance A; 5) compute coefficients of discordance using equation (5) and fill in the matrix of coefficients of discordance B; 6) determine dominance relationships and represent them graphically; if there are too many settlements, the construction of the graph becomes difficult; and 7) rank settlements based on the determined dominance relationships.
Also, there were no more types of dominance relationships considered, because the comparison of two settlements when the number of weakly dominated settlements, strongly dominated settlements, and number of settlements strongly dominating them are known would be difficult, eventually requiring equivalences of the dominance relationships.
Because of the relatively high levels of aggressiveness reported for heteromyid rodents, we expected that dominance relationships within pairs would be obvious.
Dominance relationships of the dark kangaroo mouse (Microdipodops megacephalus) and the little pocket mouse (Perognathus longimembris) in captivity.
For any two distribution functions F and G the following stochastic dominance relationships are defined.
It turns out that the measure of risk aversion plays a very critical role in characterizing a change in risk that may be represented by higher order stochastic dominance relationships.
In a group environment, dominance relationships are more difficult to tease apart owing to multiple interactions between individuals in the group, whereas in pairs there are fewer social variables contributing to an animal's behavior.
In the laboratory, stable dominance relationships form readily between pairs of lobsters (1, 2, 4), and hierarchies form within groups (5, 6, 7, 8).