AGB 121: Principles of Animal Genetics and Population Genetics (2+1)

INTERACTION DEVIATION

• When only a single locus is under consideration, the genotypic value is made up of breeding value and dominance deviation only.
  • G = A + D
• Metric traits are polygenic in inheritance and the genotype refers to more than one locus, the genotypic value may contain an additional deviation due to non-additive combination.
  • G = A + D + I
  • The deviation I is called the interaction deviation or epistatic deviation.
• We know that
  • P = G + E
• So now the phenotypic value can be partitioned as
  • P = A + D + I + E