Question
Explain polygenic inheritance with the help of an example.

Answer

Polygenic Inheritance:

  • It is a type of inheritance, in which traits are controlled by three or more genes. Such traits are called polygenic traits.
  • The phenotype reflects contribution of each allele and is also influenced by the environment.
  • For example, human skin colour. Suppose 3 genes A, B and C control skin colour with A, B, C being the dominant alleles and a, b, c being the recessive alleles. Then,

  • The F2 generation will have varied skin tones, with each type of allele in the genotype determining the darkness or lightness of the skin.

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