The Importance of the Prenatal Environment in Behavioral Genetics: Introduction to Special Issue

Abstract

We introduce and discuss a special issue on prenatal factors in genetics research, that includes 14 papers ranging from studies on chorionicity, smoking during pregnancy, and more general prenatal risks to papers about theory, methods and measurement. There are two review papers, one focused on chorioncity and the second on pre- and perinatal ischemia-hypoxia, that help to frame the state of research in these areas with a focus on the relevance across multiple fields of study. Taken together, these papers clearly demonstrate the importance of considering prenatal environment influences on functioning in offspring across the lifespan while also underscoring the importance of using genetically informed designs as a means to clarify causality.

Child Effects on Parental Negativity: The Role of Heritable and Prenatal Factors

“…In addition, few studies have considered in parallel the effects of heritable and prenatal factors on child effects on parental negativity. Previous work using the same parentoffspring adoption sample as this study indicates prenatal effects (e.g., perinatal internalizing symptoms, prenatal and neonatal complications) on toddlers' behaviors (Marceau, Hajal, et al, 2013;Neiderhiser et al, 2016;Roben et al, 2015), although these studies have mainly focused on toddlers' problem behaviors rather than temperamental characteristics. In addition, previous work has shown evocative rGE effects on parenting during early childhood (e.g., Elam et al, 2014;Fearon et al, 2015;Klahr et al, 2017), although many of these previous investigations did not identify specific child characteristics that mediate the association between heritable influences and parenting.…”

“…Child effects on parental negativity may also be influenced by prenatal environmental influences (e.g., Knopik, Neiderhiser, de Geus, & Boomsma, 2016). In this report, we focus on maternal illicit drug use during pregnancy as especially relevant to the development of child negative reactivity, which has been shown to evoke parental negativity.…”

“…It is important to clarify if the effects of prenatal illicit drug exposure on child functioning are confounded by heritable or postnatal rearing environmental influences before inferring that prenatal influences are primary (Knopik et al, 2016). Specifically, child emotional and behavioral outcomes that are influenced by pregnancy drug use may also be influenced by heritable factors or influenced by postnatal rearing environments (D'Onofrio et al, 2008;Neiderhiser et al, 2016). Thus, the effects of prenatal drug use on child negative reactivity drawn from studies based on biological families cannot be fully attributed to direct prenatal environmental effects.…”

Prenatal Risk and Infant Regulation: Indirect Pathways via Fetal Growth and Maternal Prenatal Stress and Anger

“…One of the most persistent effects of prenatal tobacco and marijuana exposure is on poor fetal growth, resulting in lower length, weight, and head circumference at birth (Day et al, 1992; DiFranza et al, 2004; Knopik et al, 2016). Poor fetal growth is consistently associated with difficulties in regulating arousal and the development of self-regulatory strategies in the neonatal period (Figueras et al, 2009), in infancy and in later childhood (O’Keefe et al, 2003; Van os et al, 2001).…”

Maternal pre-pregnancy weight and twins’ temperament

“…20 The influence of prenatal environment on children's temperament and behavior is probably less strong than the influence genetic factors have. 21 In general, a genetically informative study design helps controlling for a large number of confounders that might affect the results. However, the prenatal environment experienced by twins may be different from the one singletons experience.…”