Codominance


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Related to Codominance: Multiple alleles, incomplete dominance

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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A bay scallop sample (CR) obtained from a hatchery and used for mtDNA RFLP analysis by Blake and Graves (1995) also had codominant haplotypes, suggesting that the codominance of H2 and H3 we observed resulted from supplementation with hatchery bay scallops.
Blood type is an example of codominance, and coat color is an example of partial dominance.
Twenty-one of the 128 RFLP markers were dominant and the rest exhibited codominance.
The report describes a mathematical modelling activity of a natural phenomenon (transmission of hereditary characters in a codominance case) using the concept of model as a theoretical instrument.
Most AFLPs are dominant markers, although codominance was apparent for some peaks (about seven loci), where A/A and A/a genotypes were distinguishable by dosage or peak height (Fig.
Yucca may be in codominance with Larrea, Coleogyne, or Juniperus (Turner 1982).
gene heredity mutation mitosis embryo allele helix clone sequence polymer autosome phenotype recessive metaphase locus polymerase telophase oligonucleotide geneticist interphase prophase phage bacteriophage chromomere transduction transformation nucleus Mendelian genome meiosis chromosome recombinant pedigree plasmid vector replicon nucleosome chromatography zygote centromere anaphase genotype endonuclease backcross exonuclease polyploidy diakinesis cytogenetics crossover segregate codominance dominance translocation nucleolus
Reciprocal replacement and the maintenance of codominance in a beech-maple forest.
In the latter, changes in community composition over the last 12,000 years are consistently characterized by the alternation and codominance of Quercus and Pinus (Costa et al.
Incomplete Dominance--A kind of inheritance where a gene does not completely cover up or modify the expression of its allele; also may be known as codominance or blending inheritance.
In SSI, codominance or dominance relations between SI alleles in the ovule-parent determine the style phenotype, whereas similar or different codominance or dominance relations in the pollen-parent determine the pollen phenotype (Ockendon 1974; Kowyama et al.
5] In vitro, both parents of hypersensitive individuals have demonstrated intermediate cell death, which suggests an autosomal codominance inheritance pattern.