Question

Why is dark skin dominant?

Answer 1

Dark skin dominant:

1. Each dominant allele expresses a portion of a functional polypeptide in quantitative inheritance, and the whole characteristic only manifests when all the dominant alleles are present.
2. Polygenes are genes involved in quantitative inheritance.
3. An example of polygenic inheritance is skin color. The pigment melanin, which is responsible for giving skin its color, is present in all skin.
4. Three (plus two additional) gene pairs control the amount of melanin that develops in an individual where dark skin alleles are A, B, and C and light skin alleles are a, b and c.
5. The genes for the skin pigment melanin are located at three separate loci, and each dominant gene—not a recessive one—is in charge of producing a set amount of melanin.
6. Each gene has an additive impact, and the quantity of melanin produced is always inversely correlated with the number of dominant genes.