Model extensions presented here illustrate the excess and transient nature of heterozygosity in the F1 generation that is partially responsible for the unique performance benefit of F1 hybrids. Mechanistically, the theory illustrates that heterosis is a function of two separate and independent mechanisms, population structure and gene action, both of which need to be considered in understanding the mechanisms of heterosis.
Aguilar et al. (Tue,) studied this question.