Answer:
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The given condition represents the phenomenon of codominant alleles.
Codominant refers to the allelic interaction none of the alleles is dominant over each other completely.
It leads to the blending of the traits as both the alleles codes for their traits.
For example,
and
results in the blending of traits which results in the production of blood group AB.
Similarly, in snapdragon red and white traits are blended to produce pink colored flowers.