When a dominant allele coexists with a recessive allele in a heterozygote individual, how do they interact with each other?

Question

A. They do not interact at all.
B. The dominant allele prevents transcription of the recessive allele.

Answer 1

The correct answer is:

A. They do not interact at all.

In a heterozygote individual, where one allele is dominant and the other is recessive, the dominant allele's phenotype is expressed while the recessive allele's phenotype is masked. This does not mean that the recessive allele is prevented from being transcribed at the molecular level; rather, the expression of the recessive phenotype is not visible when paired with a dominant allele. The dominant allele typically produces a functional product (like a protein) that exerts its effect, while the recessive allele may not produce a product that affects the phenotype, or it may produce a non-functional product. However, both alleles can be present and expressed at the genetic level without directly interfering with each other's transcription.