The Drosophila foraging gene human orthologue PRKG1 predicts individual differences in the effects of early adversity on maternal sensitivity

Abstract

There is variation in the extent to which childhood adverse experience affects adult individual differences in maternal behavior. Genetic variation in the animal foraging gene, which encodes a cGMP-dependent protein kinase, contributes to variation in the responses of adult fruit flies, Drosophila melanogaster, to early life adversity and is also known to play a role in maternal behavior in social insects. Here we investigate genetic variation in the human foraging gene (PRKG1) as a predictor of individual differences in the effects of early adversity on maternal behavior in two cohorts. We show that the PRKG1 genetic polymorphism rs2043556 associates with maternal sensitivity towards their infants. We also show that rs2043556 moderates the association between self-reported childhood adversity of the mother and her later maternal sensitivity. Mothers with the TT allele of rs2043556 appeared buffered from the effects of early adversity, whereas mothers with the presence of a C allele were not. Our study used the Toronto Longitudinal Cohort (N=288 mother−16 month old infant pairs) and the Maternal Adversity and Vulnerability and Neurodevelopment Cohort (N=281 mother−18 month old infant pairs). Our findings expand the literature on the contributions of both genetics and gene-environment interactions to maternal sensitivity, a salient feature of the early environment relevant for child neurodevelopment.

Self-regulation and the foraging gene ( PRKG1 ) in humans

“…Sample 2. Sample 1 results suggested an association between RMP and genetic variants in PRKG1 (7,11,19,26). Next, we aimed to replicate our findings in a larger sample while measuring search behaviors on an experimental analog of foraging.…”

“…PRKG1 proteins are found across the nervous system and are thought to underpin neuroplasticity and learning (25), and likely influence behavior in myriad ways. Variation in PRKG1 was recently associated with interactions between maternal sensitivity and early life adversity (26) and between alcoholism and trauma (27).…”

Epigenetic mechanisms modulate differences in Drosophila foraging behavior

“…for regulates various behavioral and physiological phenotypes in the fly and other organisms, including humans (4)(5)(6)(7)(8)(9). Importantly, this gene, with its rover and sitter allelic variants, is known to give rise to naturally occurring behavioral variations in D. melanogaster.…”

Gene–Environment Interplay and Individual Differences in Behavior

“…(Examples are provided in the next paragraph.) G×E studies of this type use specific genetic variants of a candidate gene and correlate this to an environmental measure such as early adversity (e.g., H. M. Sokolowski et al, ). Nominated candidate genes often come from the animal literature and it is important to know enough about the human trait to erect a hypothesis about a particular candidate gene.…”

“…(Examples are provided in the next paragraph.) G×E studies of this type use specific genetic variants of a candidate gene and correlate this to an environmental measure such as early adversity (e.g., H. M. Sokolowski et al, 2017 Risch et al, 2009;Rutter, 2010). Studies can fail to replicate G×E interactions because of lack of standardization of environmental and phenotypic assessment, statistical methods, and study designs (Dunn et al, 2011).…”