Question

Skin colour is controlled by

• A. Single gene
• B. 3 pairs of genes
• C. 2 pairs of genes
• D. 2 pairs of genes with an intragene

Answer 1

Answer: (B)

3 pairs of genes

Human skin colour is a polygenic trait governed by three pairs of genes (Aa, Bb and Cc) where dominant allele of each gene express only a part of trait and the full trait is expressed only in presence of dominant alleles of all multiple genes, is called polygenic inheritance. These genes control skin pigmentation only, no other phenotypic trait is affected by these genes. Thus, the correct answer is option B.