Dividing the child.

The evolution of genomic imprinting is viewed as a problem of economic optimization that is analyzed using the tools of evolutionary game theory. We specifically consider genetic conflicts over the allocation of maternal resources between present and future offspring. Five sets of genes, with the same interests within sets but distinct interests between sets, are considered as agents: maternal alleles (Mater), paternal alleles (Pater), unimprinted offspring alleles (Filius), and imprinted offspring alleles of maternal and paternal origin (Matris and Patris). Fitness functions are derived for each agent and the parameter space in which there is conflict defined. Three potential conflicts are considered: between mother and offspring (Mater v.s. Filius); between alleles of maternal and paternal origin within offspring (Matris v.s. Patris) and between mothers and the paternally derived alleles of offspring (Mater v.s. Patris).