Paternal adverse childhood experiences: Associations with infant DNA methylation

Maternal Childhood Adversity and Infant Epigenetic Aging: Moderation by Restless Sleep During Pregnancy

Maternal exposure to childhood adversity is associated with detrimental health outcomes throughout the lifespan and may have implications for offspring. Evidence links maternal adverse childhood experiences (ACEs) to detrimental birth outcomes, yet the impact on the infant's epigenome is unclear. Moreover, maternal sleep habits during pregnancy may influence this association. Here, we explore whether restless sleep during pregnancy moderates the association between exposure to maternal childhood adversity and infant epigenetic age acceleration in 332 mother-infant dyads (56% female; 39% Black; 25% Hispanic). During the 2nd trimester, mothers self-reported childhood adversity and past-week restless sleep; DNA methylation from umbilical vein endothelial cells was used to estimate five epigenetic clocks. Multivariable linear regression was used to test study hypotheses. Despite no evidence of main effects, there was evidence of an interaction between maternal ACEs and restless sleep in predicting infant epigenetic age acceleration using the EPIC Gestational Age clock. Only infants whose mothers reported exposure to both ACEs and restless sleep demonstrated accelerated epigenetic aging. Results provide preliminary evidence that maternal childhood adversity and sleep may influence the infant epigenome.

Sex-Specific Associations between Prenatal Exposure to Di(2-ethylhexyl) Phthalate, Epigenetic Age Acceleration, and Susceptibility to Early Childhood Upper Respiratory Infections

Di(2-ethylhexyl) phthalate (DEHP) is a common plasticizer that can affect immune system development and susceptibility to infection. Aging processes (measured as epigenetic age acceleration (EAA)) may mediate the immune-related effects of prenatal exposure to DEHP. This study's objective was to examine associations between prenatal DEHP exposure, EAA at three months of age, and the number of upper respiratory infections (URIs) from 12 to 18 months of age using a sample of 69 maternal-child pairs from a Canadian pregnancy cohort. Blood DNA methylation data were generated using the Infinium HumanMethylation450 BeadChip; EAA was estimated using Horvath's pan-tissue clock. Robust regressions examined overall and sex-specific associations. Higher prenatal DEHP exposure (B = 6.52, 95% CI = 1.22, 11.81) and increased EAA (B = 2.98, 95% CI = 1.64, 4.32) independently predicted more URIs. In sex-specific analyses, some similar effects were noted for boys, and EAA mediated the association between prenatal DEHP exposure and URIs. In girls, higher prenatal DEHP exposure was associated with decreased EAA, and no mediation was noted. Higher prenatal DEHP exposure may be associated with increased susceptibility to early childhood URIs, particularly in boys, and aging biomarkers such as EAA may be a biological mechanism. Larger cohort studies examining the potential developmental immunotoxicity of phthalates are needed.

Assessment of aberrant DNA methylation two years after paediatric critical illness: a pre-planned secondary analysis of the international PEPaNIC trial

Critically ill children requiring intensive care suffer from impaired physical/neurocognitive development 2 y later, partially preventable by omitting early use of parenteral nutrition (early-PN) in the paediatric intensive-care-unit (PICU). Altered methylation of DNA from peripheral blood during PICU-stay provided a molecular basis hereof. Whether DNA-methylation of former PICU patients, assessed 2 y after critical illness, is different from that of healthy children remained unknown. In a pre-planned secondary analysis of the PEPaNIC-RCT (clinicaltrials.gov-NCT01536275) 2-year follow-up, we assessed buccal-mucosal DNA-methylation (Infinium-HumanMethylation-EPIC-BeadChip) of former PICU-patients (N = 406 early-PN; N = 414 late-PN) and matched healthy children (N = 392). CpG-sites differentially methylated between groups were identified with multivariable linear regression and differentially methylated DNA-regions via clustering of differentially methylated CpG-sites using kernel-estimates. Analyses were adjusted for technical variation and baseline risk factors, and corrected for multiple testing (false-discovery-rate <0.05). Differentially methylated genes were functionally annotated (KEGG-pathway database), and allocated to three classes depending on involvement in physical/neurocognitive development, critical illness and intensive medical care, or pre-PICU-admission disorders. As compared with matched healthy children, former PICU-patients showed significantly different DNA-methylation at 4047 CpG-sites (2186 genes) and 494 DNA-regions (468 genes), with most CpG-sites being hypomethylated (90.3%) and with an average absolute 2% effect-size, irrespective of timing of PN initiation. Of the differentially methylated KEGG-pathways, 41.2% were related to physical/neurocognitive development, 32.8% to critical illness and intensive medical care and 26.0% to pre-PICU-admission disorders. Two years after critical illness in children, buccal-mucosal DNA showed abnormal methylation of CpG-sites and DNA-regions located in pathways known to be important for physical/neurocognitive development.

Intergenerational Transmission of Parental Adverse Childhood Experiences and Children's Outcomes: A Scoping Review

Adverse childhood experiences (ACEs) are among the leading environmental causes of morbidity and mortality. Extending research on within-generation effects, more recent scholarship has explored between-generation consequences of ACEs. Despite growing interest in the intergenerational effects of parents' ACEs on children's outcomes, this line of scholarship has yet to be coalesced into a comprehensive review. The current study is a scoping review on the intergenerational transmission of parental ACEs and children's outcomes. Ten databases such as PubMed, APA PsycArticles, and Social Work Abstracts were searched. To be included, empirical studies must have been published in English and analyzed associations between a cumulative measure of at least four parental ACEs and children's outcomes. Sixty-eight studies qualified for the review and, among these, 60 were published in the most recent 5 years (2018-2022). Fifty-one studies had sample sizes smaller than 500, and 55 focused on the effect of maternal ACEs. Nearly all studies demonstrated that parental ACEs could affect children's outcomes directly or indirectly via mechanisms like maternal mental health problems or parenting-related factors. By scoping the extant literature, this review advances the knowledge base regarding the intergenerational impacts of parental childhood trauma and children's outcomes. It also reveals methodological limitations that should be addressed in future research to strengthen causal inferences along with practical implications for interventions that aim to interrupt the intergenerational transmission of trauma.

Maternal adverse childhood experiences (ACEs) and DNA methylation of newborns in cord blood

BACKGROUND

Adverse childhood experiences (ACEs) increase the risk of poor health outcomes later in life. Psychosocial stressors may also have intergenerational health effects by which parental ACEs are associated with mental and physical health of children. Epigenetic programming may be one mechanism linking parental ACEs to child health. This study aimed to investigate epigenome-wide associations of maternal preconception ACEs with DNA methylation patterns of children. In the Center for the Health Assessment of Mothers and Children of Salinas study, cord blood DNA methylation was measured using the Illumina HumanMethylation450 BeadChip. Preconception ACEs, which occurred during the mothers' childhoods, were collected using a standard ACE questionnaire including 10 ACE indicators. Maternal ACE exposures were defined in this study as (1) the total number of ACEs; (2) the total number of ACEs categorized as 0, 1-3, and > 4; and (3) individual ACEs. Associations of ACE exposures with differential methylated positions, regions, and CpG modules determined using weighted gene co-expression network analysis were evaluated adjusting for covariates.

RESULTS

Data on maternal ACEs and cord blood DNA methylation were available for 196 mother/newborn pairs. One differential methylated position was associated with maternal experience of emotional abuse (cg05486260/FAM135B gene; q value < 0.05). Five differential methylated regions were significantly associated with the total number of ACEs, and 36 unique differential methylated regions were associated with individual ACEs (Šidák p value < 0.05). Fifteen CpG modules were significantly correlated with the total number of ACEs or individual ACEs, of which 8 remained significant in fully adjusted models (p value < 0.05). Significant modules were enriched for pathways related to neurological and immune development and function.

CONCLUSIONS

Maternal ACEs prior to conception were associated with cord blood DNA methylation of offspring at birth. Although there was limited overlap between differential methylated regions and CpGs in modules associated with ACE exposures, statistically significant regions and networks were related to genes involved in neurological and immune function. Findings may provide insights to pathways linking psychosocial stressors to health. Further research is needed to understand the relationship between changes in DNA methylation and child health.

Intergenerational transmission of parent adverse childhood experiences to child outcomes: A systematic review and meta-analysis

OBJECTIVE

The current meta-analytic review provides a comprehensive synthesis of studies examining parent exposure to ACEs and the developmental and mental health outcomes of their children.

PARTICIPANTS AND SETTING

Eligible studies up to August 2021 were identified through comprehensive database searches in PsycINFO, MEDLINE, and Embase. Studies that were included examined the intergenerational effects of parent ACEs on child development (i.e., cognitive, language, motor, social difficulties, and early social-emotional development) or mental health (i.e., internalizing problems, externalizing problems) outcomes.

METHODS

Data were extracted by two coders using a standardized extraction protocol. A multi-level meta-analytic approach was used to derive pooled effect sizes and test for moderators.

RESULTS

A total of 52 studies were included in the meta-analysis. Parent ACEs were positively associated with child mental health problems (r=0.17, 95% CI [0.12, 0.21], p<.001), child externalizing difficulties (r=0.20, 95% CI [0.15, 0.26], p<.001), and child internalizing difficulties (r=0.17, 95% CI [0.11, 0.22], p<.001). There were no significant sociodemographic (i.e., child age, parent age, income level, child sex, or racial/ethnic minority status) or methodological (i.e., study type or quality) moderators of these associations. Preliminary evidence suggests that parent ACEs were not associated with offspring developmental outcomes, such as cognitive or language skills.

CONCLUSIONS

Results suggest that parent ACEs are associated with some, but not all child outcomes. Additional research focused on the mechanisms of transmission are needed to inform policies and practices related to the intergenerational transmission of ACEs.

Transmit Radiant Individuality to Offspring (TRIO) study: investigating intergenerational transmission effects on brain development

Intergenerational transmission is a crucial aspect of human development. Although prior studies have demonstrated the continuity of psychopathology and maladaptive upbringing environments between parents and offspring, the underlying neurobiological mechanisms remain unclear. We have begun a novel neuroimaging research project, the Transmit Radiant Individuality to Offspring (TRIO) study, which focuses on biological parent-offspring trios. The participants of the TRIO study were Japanese parent-offspring trios consisting of offspring aged 10-40 and their biological mother and father. Structural and functional brain images of all participants were acquired using magnetic resonance imaging (MRI). Saliva samples were collected for DNA analysis. We obtained psychosocial information, such as intelligence, mental health problems, personality traits, and experiences during the developmental period from each parent and offspring in the same manner as much as possible. By April 2023, we completed data acquisition from 174 trios consisting of fathers, mothers, and offspring. The target sample size was 310 trios. However, we plan to conduct genetic and epigenetic analyses, and the sample size is expected to be expanded further while developing this project into a multi-site collaborative study in the future. The TRIO study can challenge the elucidation of the mechanism of intergenerational transmission effects on human development by collecting diverse information from parents and offspring at the molecular, neural, and behavioral levels. Our study provides interdisciplinary insights into how individuals' lives are involved in the construction of the lives of their descendants in the subsequent generation.

Biological Embedding of Early-Life Adversity and a Scoping Review of the Evidence for Intergenerational Epigenetic Transmission of Stress and Trauma in Humans

Severe or chronic stress and trauma can have a detrimental impact on health. Evidence suggests that early-life adversity can become biologically embedded and has the potential to influence health outcomes decades later. Epigenetics is one mechanism that has been implicated in these long-lasting effects. Observational studies in humans indicate that the effects of stress could even persist across generations, although whether or not epigenetic mechanisms are involved remains under debate. Here, we provide an overview of studies in animals and humans that demonstrate the effects of early-life stress on DNA methylation, one of the most widely studied epigenetic mechanisms, and summarize findings from animal models demonstrating the involvement of epigenetics in the transmission of stress across generations. We then describe the results of a scoping review to determine the extent to which the terms intergenerational or transgenerational have been used in human studies investigating the transmission of trauma and stress via epigenetic mechanisms. We end with a discussion of key areas for future research to advance understanding of the role of epigenetics in the legacy effects of stress and trauma.

Impacts on children's health of adverse childhood experiences of their mothers: A gender-specific mediation analysis using data from the China Health and Retirement Longitudinal Study

BACKGROUND

Numerous people have suffered adverse childhood experiences (ACEs) that can have lasting negative consequences. However, few studies have focused on maternal ACEs' effect on their children's health. This study aimed to evaluate the impact on children's health of ACEs that their mothers experienced.

METHODS

Data from the China Health and Retirement Longitudinal Study (CHARLS) 2018 combined with the CHARLS 2014 Life History Survey were analyzed. The logistic regression was used to investigate maternal ACEs' impact on their children's health. Based on the stepwise regression model and bias-corrected bootstrap, we estimated the mediating effects.

RESULTS

Maternal ACEs could result in harm to the health of children (P < 0.05). If the types of maternal ACEs increased by one unit, the odds ratio of their children's poor health would rise by 9.6 %. Moreover, if the types of maternal ACEs increased by one unit, the odds ratio of daughters' and sons' poor health would increase by 8.3 % and 10.2 %, respectively. Three mediating mechanisms of mothers' education, physical health, and mental health were confirmed by empirical tests.

LIMITATIONS

We could not employ objective indicators to measure children's health. Meanwhile, maternal ACEs were all self-reported from the mothers' recollection, which might descend the accuracy due to memory bias.

CONCLUSION

Maternal ACEs harmed the health of both their sons and daughters. The children's health would deteriorate as the maternal ACEs increased. Mother's education, physical health, and mental health mediated the relationships between maternal ACEs and children's health.

Preconception paternal mental disorders and child health: Mechanisms and interventions

Mental illness is a significant global health issue with a steady prevalence. High heritability is suspected, but genome-wide association studies only identified a small number of risk genes associated with mental disorders. This 'missing inheritance' can be partially explained by epigenetic heredity. Evidence from numerous animal models and human studies supports the possibility that preconception paternal mental health influences their offspring's mental health via nongenetic means. Here, we review two potential pathways, including sperm epigenetics and seminal plasma components. The current review highlights the role of sperm epigenetics and explores epigenetic message origination and susceptibility to chronic stress. Meanwhile, possible spatiotemporal windows and events that induce sexually dimorphic modes and effects of paternal stress transmission are inferred in this review. Additionally, we discuss emerging interventions that could potentially block the intergenerational transmission of paternal psychiatric disorders and reduce the incidence of mental illness. Understanding the underlying mechanisms by which preconception paternal stress impacts offspring health is critical for identifying strategies supporting healthy development and successfully controlling the prevalence of mental illness.

Intergenerational associations of adverse and positive maternal childhood experiences with young children's psychosocial well-being

Background: Maternal adverse childhood experiences (ACEs) are believed to have negative consequences on offspring health. However, positive childhood experiences (PCEs) may be concurrent with ACEs, and little is known about how ACEs and PCEs transmit intergenerationally in the context of each other.Objective: To explore the independent effect of maternal ACEs and PCEs on offspring psychosocial well-being and how ACEs and PCEs are intergenerationally transmitted in their context.Method: Data were 2587 mother-child dyads in Anhui provinces of China. Mothers retrospectively reported their ACEs and PCEs, as well as provided demographic characteristics and their children's psychosocial well-being. Logistic regression models were performed to explore the associations of maternal ACEs and PCEs with offspring psychosocial well-being.Results: Separate unadjusted logistic regression models showed that children with mothers reported high ACEs scores were more likely to have psychosocial challenges (total difficulties and prosocial problems), while children whose mothers reported high PCEs scores were less likely to have psychosocial challenges. When we added maternal ACEs and PCEs to a same model, we found that PCEs slightly neutralised the negative effects of ACEs on offspring's total difficulties and prosocial problems. When stratified by sample, mothers with high PCE scores and higher maternal ACEs were related with a higher risk of offspring total difficulties; mothers with low levels of ACEs and high PCEs tend to report a lower risk of offspring total difficulties.Conclusions: Results suggest that PCEs are positively and intergenerationally transmitted. Results suggest that PCEs are positively and intergenerationally transmitted. More programme should be provided to increase maternal PCEs. When preventing the intergenerational transmission of ACEs, specific interventions should be provided to mothers with different levels of PCEs.

Childhood Trauma and Epigenetics: State of the Science and Future

PURPOSE OF REVIEW

There is a great deal of interest regarding the biological embedding of childhood trauma and social exposures through epigenetic mechanisms, including DNA methylation (DNAm), but a comprehensive understanding has been hindered by issues of limited reproducibility between studies. This review presents a summary of the literature on childhood trauma and DNAm, highlights issues in the field, and proposes some potential solutions.

RECENT FINDINGS

Investigations of the associations between DNAm and childhood trauma are commonly performed using candidate gene approaches, specifically involving genes related to neurological and stress pathways. Childhood trauma is defined in a wide range of ways in several societal contexts. However, although variations in DNAm are frequently found in stress-related genes, unsupervised epigenome-wide association studies (EWAS) have shown limited reproducibility both between studies and in relating these changes to exposures. The reproducibility of childhood trauma DNAm studies, and the field of social epigenetics in general, may be improved by increasing sample sizes, standardizing variables, making use of effect size thresholds, collecting longitudinal and intervention samples, appropriately accounting for known confounding factors, and applying causal analysis wherever possible, such as "two-step epigenetic Mendelian randomization."

Canada's Colonial Genocide of Indigenous Peoples: A Review of the Psychosocial and Neurobiological Processes Linking Trauma and Intergenerational Outcomes

The policies and actions that were enacted to colonize Indigenous Peoples in Canada have been described as constituting cultural genocide. When one considers the long-term consequences from the perspective of the social and environmental determinants of health framework, the impacts of such policies on the physical and mental health of Indigenous Peoples go well beyond cultural loss. This paper addresses the impacts of key historical and current Canadian federal policies in relation to the health and well-being of Indigenous Peoples. Far from constituting a mere lesson in history, the connections between colonialist policies and actions on present-day outcomes are evaluated in terms of transgenerational and intergenerational transmission processes, including psychosocial, developmental, environmental, and neurobiological mechanisms and trauma responses. In addition, while colonialist policies have created adverse living conditions for Indigenous Peoples, resilience and the perseverance of many aspects of culture may be maintained through intergenerational processes.

Prenatal exposure to phthalates and peripheral blood and buccal epithelial DNA methylation in infants: An epigenome-wide association study

BACKGROUND

Prenatal exposure to phthalates has been associated with adverse health and neurodevelopmental outcomes. DNA methylation (DNAm) alterations may be a mechanism underlying these effects, but prior investigations of prenatal exposure to phthalates and neonatal DNAm profiles are limited to placental tissue and umbilical cord blood.

OBJECTIVE

Conduct an epigenome-wide association study (EWAS) of the associations between prenatal exposure to phthalates and DNAm in two accessible infant tissues, venous buffy coat blood and buccal epithelial cells (BECs).

METHODS

Participants included 152 maternal-infant pairs from the Alberta Pregnancy Outcomes and Nutrition (APrON) study. Maternal second trimester urine samples were analyzed for nine phthalate metabolites. Blood (n = 74) or BECs (n = 78) were collected from 3-month-old infants and profiled for DNAm using the Infinium HumanMethylation450 (450K) BeadChip. Robust linear regressions were used to investigate the associations between high (HMWPs) and low molecular weight phthalates (LMWPs) and change in methylation levels at variable Cytosine-phosphate-Guanine (CpG) sites in infant tissues, as well as the sensitivity of associations to potential confounders.

RESULTS

One candidate CpG in gene RNF39 reported by a previous study examining prenatal exposure to phthalates and cord blood DNAm was replicated. The EWAS identified 12 high-confidence CpGs in blood and another 12 in BECs associated with HMWPs and/or LMWPs. Prenatal exposure to bisphenol A (BPA) associated with two of the CpGs associated with HMWPs in BECs.

DISCUSSION

Prenatal exposure to phthalates was associated with DNAm variation at CpGs annotated to genes associated with endocrine hormone activity (i.e., SLCO4A1, TPO), immune pathways and DNA damage (i.e., RASGEF1B, KAZN, HLA-A, MYO18A, DIP2C, C1or109), and neurodevelopment (i.e., AMPH, NOTCH3, DNAJC5). Future studies that characterize the stability of these associations in larger samples, multiple cohorts, across tissues, and investigate the potential associations between these biomarkers and relevant health and neurodevelopmental outcomes are needed.

The Alberta Pregnancy Outcomes and Nutrition (APrON) longitudinal study: cohort profile and key findings from the first three years

PURPOSE

The objectives of the ongoing Canadian longitudinal cohort called the Alberta Pregnancy Outcomes and Nutrition (APrON) study are to: (1) determine the relationship between maternal nutrient intake and status before, during, after pregnancy, and (a) maternal mental health, (b) pregnancy and birth outcomes, and (c) infant/child neurodevelopment and behavior; (2) identify maternal mental health and nutrient predictors of child behaviour; and (3) establish a DNA biobank to explore genomic predictors of children's neurodevelopment and behavior. The purpose of this paper is to describe the participants, measures, and key findings on maternal and paternal mental health, maternal nutrition, and child outcomes to when children are 3 years of age.

PARTICIPANTS

Participants included mothers and their children (n=2189) and mothers' partners (usually fathers; n=1325) from whom data were collected during the period from pregnancy to when children were 3 years of age, in Alberta, Canada. More than 88% of families have been retained to take part in completed data collection at 8 years of age.

FINDINGS TO DATE

Data comprise: questionnaires completed by pregnant women/mothers and their partners on mothers', fathers' and children's health; dietary interviews; clinical assessments; linkage to hospital obstetrical records; and biological samples such as DNA. Key findings on mental health, nutrition and child outcomes are presented. APrON women who consumed more selenium and omega-3 were less likely to develop symptoms of perinatal depression. Higher prenatal consumption of choline rich foods such as eggs and milk were recommended as was vitamin D supplementation for both mothers and children to meet guidelines. Couples in which both mothers and fathers were affected by perinatal depression reported lower incomes and higher maternal prenatal depressive symptoms and lower support from fathers postnatally and their children presented with the most behavioural problems. Maternal experiences of early adversity predicted increased likelihood of perinatal depression and anxiety and children's behavioural problems.

FUTURE PLANS

The APrON cohort offers a unique opportunity to advance understanding of the developmental origins of health and disease. There is a planned follow-up to collect data at 12 years of age.