In both codominance and incomplete dominance, both alleles for a trait are dominant. In codominance a heterozygous individual expresses both simultaneously without any blending. An example of codominance is the roan cow which has both red hairs and white hairs. In incomplete dominance a heterozygous individual blends the two traits. An example of incomplete dominance is the pink snapdragon, which receives a red allele and white allele.
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