Serotonin transporter allelic variation in mothers predicts maternal sensitivity, behavior and attitudes toward 6-month-old infants

Abstract

Maternal behavior in the new mother is a multidimensional set of responses to infant cues that are influenced by the mother's early life experiences. In this study, we wanted to test if mothers' early life experiences and mothers' genotype have interactive effects on maternal behaviors and attitudes, something which has not been previously explored. In a sample of 204 mothers, we assessed maternal genotype at the serotonin transporter-linked polymorphic region (5-HTTLPR) and an adjacent upstream polymorphism (rs25531), together giving rise to three alleles: short (S), L G and L A . Controlling for maternal age and parity, we showed that this genotype can predict differences in maternal sensitivity at 6 months postpartum: mothers with an S (or the functionally similar L G ) allele were more sensitive than mothers who lacked the allele during a 30-min recorded mother-infant interaction (F (4, 140) = 3.43; P = 0.01). Furthermore, we found highly significant gene-environment interactions in association with maternal behavior, such that mothers with no S or L G alleles oriented away more frequently from their babies if they also reported more negative early care quality (F (5, 138) = 3.28; P = 0.008). Finally, we found significant gene-environment associations with maternal attitudes; mothers with the S allele and with greater early care quality scored higher on ratings of their perceived attachment to their baby (F (5, 125) = 3.27; P = 0.008).

Elucidating the etiology of individual differences in parenting: A meta-analysis of behavioral genetic research.

“…Given the many etiological factors that could infiuence parenting at the level of the parent, including spouse or coparent characteristics, child characteristics, and sociocultural factors, the confirmation of parent-driven genetic infiuences on parenting is particularly noteworthy. These results are also consistent with the handful of molecular genetic studies identifying genetic effects on parenting Burkhouse, Gibb, Coles, Knopik, & McGeary, 2011;Lee et al, 2010;Mileva-Seitz et al, 2011;Prichard, Mackinnon, Jorm, & Easteal, 2007;van IJzendoom, Bakermans-Kranenburg, & Mesman, 2008). Nevertheless, the mechanisms through which these genetic effects infiuence parental behavior in humans remain largely unknown.…”

“…Similarly, a small but growing body of molecular genetic research has begun to identify specific genetic variants that may be associated with individual differences in human parenting (although all of the existing studies have relied on relatively small samples; n < 350). In particular, several studies have reported a relationship between dopamine genes and human parenting (Hayden et al, 2010;Lee et al, 2010;Lucht et al, 2006;Mileva-Seitz et al, 2012;Mills-Koonce et al, 2007;Propper et al, 2008). In addition, both serotonin genes and OXTR have been linked to sensitive parenting Mileva-Seitz et al, 2011).Î n short, extant research provides both circumstantial (e.g., biological infiuences on parenting in nonhuman animals) and more direct (e.g., molecular genetic studies) evidence for genetic infiuences on parenting behavior.…”

Developmental changes in serotonin signaling: Implications for early brain function, behavior and adaptation

“…At 6 months postpartum, mothers with allelic variations that reduce 5-HT reuptake (the s alleles) were found to be more sensitive to their infants than mothers with two l alleles. In contrast to the G × E studies cited above, an interaction emerged whereby mothers with the l allele within a negative care experience were more likely to orient away from their infants, while mothers with the s allele and a positive care experience reported better perceived attachment (Mileva-Seitz et al, 2011). These findings raise intriguing questions about the differential effects of the allelic variations s and l alleles during the antenatal period, and how maternal 5-HT might mediate postnatal relationships with her infant and how maternal genotype shapes the infant’s early environment.…”

Gene‐environment correlations in the cross‐generational transmission of parenting: Grandparenting moderates the effect of child 5‐HTTLPR genotype on mothers' parenting

“…This possibility is consistent with recent findings from Beaver and Belsky (2012), who found that mothers who had several specific dopaminergic and serotonergic polymorphisms showed differential susceptibility to the effects of their mother’s behavior on their own parenting behavior. Along a similar vein, mothers with a short allele show less sensitivity to toddlers (Bakermans-Kranenberg & van Ijzendoorn, 2008) and report poorer quality attachment to their infant (Mileva-Seitz et al, 2011). Mothers with a short allele at 5-HTTLPR also show less sensitive parenting in the context of high levels of interparental conflict (Sturge-Apple et al, 2012).…”