Additive genetic effects

This can be stated mathematically as: VP = VE + VG, where the terms refer to variation in phenotype, environment, and genotype respectively.

[1] Broad sense heritability (H2, or HB) refers to the phenotypic differences arising from all genetic effects, and can be described as the ratio of genotypic variation to that of phenotypic variation in the population, or: H2 = VG / VP.

In the study of Heritability, Additive genetic effects are of particular interest in the fields of Conservation, and Artificial selection.

The effects of dominance and epistasis are not reliably transmitted to progeny (see Mendelian inheritance, laws of segregation and independent assortment).

This Theorem suggests that where a trait affects individual fitness, the amount of variation due to additive genetic effects will decline with each successive generation, and all other things being equal, will approach zero.

This model illustrates polygenic additive effects on phenotype
Visualization of the decreasing variation of additive effects to mean fitness over generations.