Imprinted genes and the manipulation of parenting in mammals

Abstract

Genomic imprinting refers to the parent-of-origin expression of genes, which originates from epigenetic events in the mammalian germ line. The evolution of imprinting may reflect a conflict over resource allocation early in life, with silencing of paternal genes in offspring soliciting increased maternal provision and silencing of maternal genes limiting demands on the mother. Parental caregiving has been identified as an area of potential conflict, with several imprinted genes serendipitously found to directly influence the quality of maternal care. Recent systems biology approaches, based on single-cell RNA sequencing data, support a more deliberate relationship, which is reinforced by the finding that imprinted genes expressed in the offspring influence the quality of maternal caregiving. These bidirectional, reiterative relationships between parents and their offspring are critical both for short-term survival and for lifelong wellbeing, with clear implications for human health. Genomic imprinting — the monoallelic expression of genes based on their parent of origin — may have evolved due to an intragenomic conflict between maternal and paternal genomes within an individual, with differential interests regarding the level of parental caregiving. Here, the authors review the influence of genomic imprinting on parenting behaviour in mammals, with a focus on studies in mice.