Duplicate Factor

What is Duplicate Factor? – Definition

  • Involves two pairs of non-allelic genes
  • Affect the same character
  • Dominant form of both genes, either alone or in combination produce same phenotypic expression.
  • Recessive forms of both the genes when together produce different phenotypic effect.
  • Duplicate factor interaction is observed in awned and awnless condition in rice.

In case of rice when pure breeding awned plant is crossed with awnless, the progeny was awned.

In F2 segregation was observed in the ratio of 15 awned: 1 awnless. This behavior is based on ratio of dihybrid cross, so the trait must be governed by two pairs of genes.

Suppose, A1 and A2 are two duplicate factors.

Genotype of pure breeding awned plant must be A1A1A2A2, as it is dominant and genotype of awnless plant must be a1a1a2a2 as it is recessive.

Cross between F1 F2
A1A1A2A2 X a1a1a2a2
awned X awnless
A1a1A2a2
awned
15 awned : 1 awnless

To know other types of gene interactions like duplicate factor visit page Gene Interaction types.