Early experience and parent-of-origin-specific effects influence female reproductive success in mice.

Recent studies on mammals investigating parent-of-origin-specific effects such as genomic imprinting and maternal effects have demonstrated their impact on short-term measures of fitness, for example offspring growth. However, the long-term fitness consequences of parent-of-origin-specific effects and their role outside the immediate mother-offspring interaction remain largely unexplored. Here, we show that female mice mated to males that inherited the same set of paternal and maternal genes as themselves have a higher reproductive success than females mated to males of reciprocal genotype. Furthermore, we demonstrate that the early social environment experienced by an individual influences its reproductive success. Females raised with unrelated siblings in a mixed litter had a subsequent lower reproductive success than those that were fostered together with all their biological siblings in unmixed litters. Our results highlight the important influence of parent-of-origin-specific effects and conditions in early development on long-term reproductive success in mammals and suggest that parent-of-origin-specific effects may provide the underlying mechanism for beneficial coadaptation between genotypes, for example, in mate choice.