Co-dominance in the mn blood group means that both allele characteristics are expressed in the organism.
Co-dominance is a form of inheritance whereby two or more alleles for a given trait are both dominant such that when they both appear in an organism, the phenotype of that organism reflects the characteristic of both traits.
Co-dominance is usually seen in blood group typing.
In blood group typing, there are two alleles that A and B which are both dominant. When both alleles are present, the blood group is AB and the phenotype of the organism is a result of the properties of both alleles, thus allele A and B are said to be co-dominant.
Therefore, co-dominance in the mn blood group means that both allele characteristic are expressed in the organism.
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