The public reception of putative epigenetic mechanisms in the transgenerational effects of trauma

Refusing epigenetics: indigeneity and the colonial politics of trauma

Environmental epigenetics is increasingly employed to understand the health outcomes of communities who have experienced historical trauma and structural violence. Epigenetics provides a way to think about traumatic events and sustained deprivation as biological "exposures" that contribute to ill-health across generations. In Australia, some Indigenous researchers and clinicians are embracing epigenetic science as a framework for theorising the slow violence of colonialism as it plays out in intergenerational legacies of trauma and illness. However, there is dispute, contention, and caution as well as enthusiasm among these research communities.In this article, we trace strategies of "refusal" (Simpson, 2014) in response to epigenetics in Indigenous contexts. Drawing on ethnographic fieldwork conducted in Australia with researchers and clinicians in Indigenous health, we explore how some construct epigenetics as useless knowledge and a distraction from implementing anti-colonial change, rather than a tool with which to enact change. Secondly, we explore how epigenetics narrows definitions of colonial harm through the optic of molecular trauma, reproducing conditions in which Indigenous people are made intelligible through a lens of "damaged" bodies. Faced with these two concerns, many turn away from epigenetics altogether, refusing its novelty and supposed benefit for Indigenous health equity and resisting the pull of postgenomics.

Epigenetics of Trauma Transmission and Fetal Alcohol Spectrum Disorder: What Does the Evidence Support?

Fetal alcohol spectrum disorder (FASD) results from teratogenic impacts of alcohol consumption during pregnancy. Trauma and prenatal alcohol exposure (PAE) can both cause neurodevelopmental impairment, and it has been proposed that FASD can amplify effects of trauma. Certain PAE and trauma effects are mediated via epigenetic mechanisms. The objective of this review is to present the current evidence for epigenetics in trauma transmission as it relates to FASD, to help bridge a potential knowledge gap for social workers and related health professionals. We include a primer on epigenetic mechanisms and inheritance, followed by a summary of the current biomedical evidence supporting intergenerational and transgenerational epigenetic transmission of trauma, its relevance to FASD, the intersection with social transmission, and finally the application to social work. We propose potential models of transmission, considering where social and epigenetic pathways may intersect and/or compound across generations. Overall, we aim to provide a better understanding of epigenetic-trauma transmission for its application to health professions, in particular which beliefs are (and are not) evidence-based. We discuss the lack of research and challenges of studying epigenetic transmission in humans and identify the need for public health interventions and best practices that are based on the current evidence.

Birth-related PTSD symptoms and related factors following preterm childbirth in Turkey

Objective: To examine factors associated with birth-related post-traumatic stress disorder (PTSD) among women who had preterm birth in their last pregnancy in Turkey.Methods: 304 women were asked to report sociodemographic factors, perinatal factors, birth-related factors, preterm birth/premature infant characteristics, and social support factors and PTSD symptoms. Data were collected using online surveys between November 2020 and February 2021. Hierarchical multiple linear regression was used. Results: The prevalence of birth-related PTSD symptoms following preterm birth was 71.1%. Older age, the woman being positively affected by her own mother's birth experience, not having traumatic experience in pregnancy and in the postnatal period, lower stress level after traumatic events experienced during birth, not feeling that their life/physical integrity was at risk during birth, having amniotomy, feeling psychologically well after childbirth, not being negatively affected by witnessing other parents' happy moments with their babies in friend/family groups, the absence of infant illness and mother's reporting higher positive interactions with healthcare team were associated with decreased likelihood of birth-related PTSD. Except for age and traumatic event in the postnatal period, all the variables explained 43% of the variance with a small effect size (f 2  = 0.04). Stress level after the traumatic events experienced during labor was the strongest predictor of birth-related PTSD symptoms (β = 0.33). Conclusion: Wellbeing of mother and baby, facilitating interventions at labor, and positive communication with the healthcare team was associated with lower birth-related PTSD symptoms. The study findings highlighted on birth-related PTSD symptoms in mothers of preterm infants in Turkey.

The roots of paternal depression: Experienced and nonexperienced trauma or Folie a Deux?

The transition to fatherhood may be challenged with anxiety and trepidation. A high prevalence has been found for paternal depression and it is reactive to maternal depression. This review aims to address potential sources of paternal depression, which may have adverse consequences on child development. We describe through three hypotheses how fathers may be at risk of depression during the transition to fatherhood: (1) psychological (interacting with ecological systems); (2) brain functional∖structural changes; and (3) (epi)genomic. We propose that paternal stressful experiences during the transition to fatherhood may be the source for paternal depression through direct stressful paternal experiences or via (potential, currently debated) nonexperienced (by the father) epigenomic transgenerational transmission. On the other hand, we suggest that resilient fathers may undergo a transient dysphoric period affected by identifying with the newborn's vulnerability as well as with the mother's postpartum vulnerability resulting in "paternity blues." In accordance with recent views on paternal "heightened sensitivity" toward the infant, we propose that the identification of both parents with the vulnerability of the newborn creates a sensitive period of Folie a Deux (shared madness) which may be a healthy transient, albeit a quasi-pathological period, recruited by the orienting response of the newborn for survival.

Resilience: Safety in the Aftermath of Traumatic Stressor Experiences

The relationship between adverse experiences and the emergence of pathology has often focused on characteristics of the stressor or of the individual (stressor appraisals, coping strategies). These features are thought to influence multiple biological processes that favor the development of mental and physical illnesses. Less often has attention focused on the aftermath of traumatic experiences, and the importance of safety and reassurance that is necessary for longer-term well-being. In some cases (e.g., post-traumatic stress disorder) this may be reflected by a failure of fear extinction, whereas in other instances (e.g., historical trauma), the uncertainty about the future might foster continued anxiety. In essence, the question becomes one of how individuals attain feelings of safety when it is fully understood that the world is not necessarily a safe place, uncertainties abound, and feelings of agency are often illusory. We consider how individuals acquire resilience in the aftermath of traumatic and chronic stressors. In this respect, we review characteristics of stressors that may trigger particular biological and behavioral coping responses, as well as factors that undermine their efficacy. To this end, we explore stressor dynamics and social processes that foster resilience in response to specific traumatic, chronic, and uncontrollable stressor contexts (intimate partner abuse; refugee migration; collective historical trauma). We point to resilience factors that may comprise neurobiological changes, such as those related to various stressor-provoked hormones, neurotrophins, inflammatory immune, microbial, and epigenetic processes. These behavioral and biological stress responses may influence, and be influenced by, feelings of safety that come about through relationships with others, spiritual and place-based connections.

An epigenetic, transgenerational model of increased mental health disorders in children, adolescents and young adults

Prevalence rates of mental health disorders in children and adolescents have increased two to threefold from the 1990s to 2016. Some increase in prevalence may stem from changing environmental conditions in the current generation which interact with genes and inherited genetic variants. Current measured genetic variant effects do not explain fully the familial clustering and high heritability estimates in the population. Another model considers environmental conditions shifting in the previous generation, which altered brain circuits epigenetically and were transmitted to offspring via non-DNA-based mechanisms (intergenerational and transgenerational effects). Parental substance use, poor diet and obesity are environmental factors with known epigenetic intergenerational and transgenerational effects, that regulate set points in brain pathways integrating sensory-motor, reward and feeding behaviors. Using summary statistics for eleven neuropsychiatric and three metabolic disorders from 128,989 families, an epigenetic effect explains more of the estimated heritability when a portion of parental environmental effects are transmitted to offspring alongside additive genetic variance.

Evidence for germline non-genetic inheritance of human phenotypes and diseases

It is becoming increasingly apparent that certain phenotypes are inherited across generations independent of the information contained in the DNA sequence, by factors in germ cells that remain largely uncharacterized. As evidence for germline non-genetic inheritance of phenotypes and diseases continues to grow in model organisms, there are fewer reports of this phenomenon in humans, due to a variety of complications in evaluating this mechanism of inheritance in humans. This review summarizes the evidence for germline-based non-genetic inheritance in humans, as well as the significant challenges and important caveats that must be considered when evaluating this process in human populations. Most reports of this process evaluate the association of a lifetime exposure in ancestors with changes in DNA methylation or small RNA expression in germ cells, as well as the association between ancestral experiences and the inheritance of a phenotype in descendants, down to great-grandchildren in some cases. Collectively, these studies provide evidence that phenotypes can be inherited in a DNA-independent manner; the extent to which this process contributes to disease development, as well as the cellular and molecular regulation of this process, remain largely undefined.

Advancing Indigenous Mental Health Research: Ethical, conceptual and methodological challenges

The articles in this issue of Transcultural Psychiatry point the way toward meaningful advances in mental health research pertaining to Indigenous peoples, illuminating the distinctive problems and predicaments that confront these communities as well as unrecognized or neglected sources of well-being and resilience. As we observe in this introductory essay, future research will benefit from ethical awareness, conceptual clarity, and methodological refinement. Such efforts will enable additional insight into that which is common to Indigenous mental health across settler societies, and that which is specific to local histories, cultures and contexts. Research of this kind can contribute to nuanced understandings of developmental pathways, intergenerational effects, and community resilience, and inform policy and practice to better meet the needs of Indigenous individuals, communities and populations.

The applied implications of epigenetics in anxiety, affective and stress-related disorders - A review and synthesis on psychosocial stress, psychotherapy and prevention

Mental disorders are highly complex and multifactorial in origin, comprising an elaborate interplay of genetic and environmental factors. Epigenetic mechanisms such as DNA modifications (e.g. CpG methylation), histone modifications (e.g. acetylation) and microRNAs function as a translator between genes and the environment. Indeed, environmental influences such as exposure to stress shape epigenetic patterns, and lifetime experiences continue to alter the function of the genome throughout the lifespan. Here, we summarize the recently burgeoning body of research regarding the involvement of aberrant epigenetic signatures in mediating an increased vulnerability to a wide range of mental disorders. We review the current knowledge of epigenetic changes to constitute useful markers predicting the clinical response to psychotherapeutic interventions, and of psychotherapy to alter - and potentially reverse - epigenetic risk patterns. Given first evidence pointing to a transgenerational transmission of epigenetic information, epigenetic alterations arising from successful psychotherapy might be transferred to future generations and thus contribute to the prevention of mental disorders. Findings are integrated into a multi-level framework highlighting challenges pertaining to the mechanisms of action and clinical implications of epigenetic research. Promising future directions regarding the prediction, prevention, and personalized treatment of mental disorders in line with a 'precision medicine' approach are discussed.

Air pollution-induced placental alterations: an interplay of oxidative stress, epigenetics, and the aging phenotype?

According to the "Developmental Origins of Health and Disease" (DOHaD) concept, the early-life environment is a critical period for fetal programming. Given the epidemiological evidence that air pollution exposure during pregnancy adversely affects newborn outcomes such as birth weight and preterm birth, there is a need to pay attention to underlying modes of action to better understand not only these air pollution-induced early health effects but also its later-life consequences. In this review, we give an overview of air pollution-induced placental molecular alterations observed in the ENVIRONAGE birth cohort and evaluate the existing evidence. In general, we showed that prenatal exposure to air pollution is associated with nitrosative stress and epigenetic alterations in the placenta. Adversely affected CpG targets were involved in cellular processes including DNA repair, circadian rhythm, and energy metabolism. For miRNA expression, specific air pollution exposure windows were associated with altered miR-20a, miR-21, miR-146a, and miR-222 expression. Early-life aging markers including telomere length and mitochondrial DNA content are associated with air pollution exposure during pregnancy. Previously, we proposed the air pollution-induced telomere-mitochondrial aging hypothesis with a direct link between telomeres and mitochondria. Here, we extend this view with a potential co-interaction of different biological mechanisms on the level of placental oxidative stress, epigenetics, aging, and energy metabolism. Investigating the placenta is an opportunity for future research as it may help to understand the fundamental biology underpinning the DOHaD concept through the interactions between the underlying modes of action, prenatal environment, and disease risk in later life. To prevent lasting consequences from early-life exposures of air pollution, policy makers should get a basic understanding of biomolecular consequences and transgenerational risks.

Fanon's Police Inspector

Frantz Fanon practiced psychiatry in a colonized Algeria during its struggle for independence. In his 1961 work The Wretched of the Earth, Fanon described cases from his treatment of Algerian nationalists and French colonists. I present one of Fanon's cases as an ethical inquiry into posttraumatic stress disorder (PTSD). A French police inspector, who is employed in torture, visits Fanon with symptoms of PTSD after escalating domestic violence. The patient asks Fanon "to help him torture … with a total peace of mind." Is it possible to treat the inspector in a meaningful way? More broadly, how might researchers and clinicians balance collective responsibilities to individual symptoms and social conditions? The answer depends on how trauma is framed: as disorder of meaning-making or circuit dysfunction, as individual illness or social rupture, as potentially gendered and racialized. These framings can reveal different views on the allocation of responsibility for the causation, expression and management of PTSD. I do not propose that it is inherently immoral to modify traumatic memories; nor do I question the efficacy of individual interventions. Rather, I ask whether PTSD has a social meaning that transcends individual comfort in decision making about erasure. What do individual interventions accomplish in the absence of concurrent political and social transformations? I argue that a holistic understanding of PTSD entails a set of social obligations: to address at its root political, gendered, and racialized violence, to repudiate occupations centered on exploitative manipulation of individuals and cultures, and to social change that prioritizes these commitments.

Intergenerational Effects of Alcohol: A Review of Paternal Preconception Ethanol Exposure Studies and Epigenetic Mechanisms in the Male Germline

While alcohol use disorder (AUD) is a highly heritable psychiatric disease, efforts to elucidate that heritability by examining genetic variation (e.g., single nucleotide polymorphisms) have been insufficient to fully account for familial AUD risk. Perhaps not coincidently, there has been a burgeoning interest in novel nongenomic mechanisms of inheritance (i.e., epigenetics) that are shaped in the male or female germ cells by significant lifetime experiences such as exposure to chronic stress, malnutrition, or drugs of abuse. While many epidemiological and preclinical studies have long pointed to a role for the parental preconception environment in offspring behavior, over the last decade many studies have implicated a causal relationship between the environmentally sensitive sperm epigenome and intergenerational phenotypes. This critical review will detail the heritable effects of alcohol and the potential role for epigenetics.

Maternal rotating night shift work before pregnancy and offspring stress markers

BACKGROUND

Recent studies suggest an intergenerational influence of stress such that maternal exposure even before pregnancy could impact offspring health outcomes later in life. In humans, investigations on the impact of maternal stressors on offspring health outcomes, including stress-sensitive biomarkers, have largely been limited to extreme stressors. Prior studies have not addressed more moderate maternal stressors, such as rotating night shift work, on offspring stress markers in young adulthood.

METHODS

We investigated the association between maternal rotating night shift work before conception and offspring salivary cortisol and alpha amylase (sAA) patterns in young adulthood among mothers enrolled in the Nurses' Health Study II (NHSII) and their offspring participating in the Growing Up Today Study 2 (GUTS2). Our sample included over 300 mother-child pairs where, between 2011 and 2014, the children provided 5 saliva samples over the course of one day. We used piecewise linear mixed models to compare awakening responses, overall slopes as well as several other diurnal patterns of cortisol and sAA between offspring born to shift working versus non-shift working mothers.

RESULTS

Offspring born to shift working mothers had a flattened late decline in cortisol (percent differences in slope (%D): 2.1%; 95%CI: 0.3, 3.8) and their sAA awakening response was steeper (%D -37.4%; 95%CI: -59.0, -4.4), whereas sAA increase before bedtime appeared less pronounced (%D -35.9%; 95%CI: -55.3, -8.3), compared to offspring born to mothers without shift work. For cortisol, we observed a significant difference in the Area Under the Curve (AUC) (%D 1.5%; 95%CI: 0.3, 2.7) with higher AUC for offspring of mothers who worked rotating night shifts. In offspring-sex-stratified analyses we found differences primarily among males.

CONCLUSION

Our results provide some - albeit modest - evidence that maternal rotating night shift work-a moderate stressor-influences offspring stress markers. Future studies with larger samples sizes, more detailed exposure assessment (particularly during maternal pregnancy), and multiple offspring biomarker assessments at different developmental stages are needed to further investigate these associations.

Epigeneti-What? Approaches on Translating Research for Primary Breast Cancer Prevention

In fiscal year 2017, the National Cancer Institute devoted more than a half billion dollars to breast cancer research. Since 2012, the total investment has been more than $3 billion. Despite this significant investment, breast cancer still has no known immediate causes as it generally develops over the life course. Therefore, research is unable to provide the public any sort of magic bullet, or conclusive link between certain environmental exposures and the development of breast cancer later in life. What research is only able to report are likelihoods—possible links—things people might want to consider avoiding or doing in their everyday lives to reduce their future risks of developing breast cancer. This abundance of rigorously performed, albeit causally inconclusive, research focused on “plausible” links poses a challenge for health communicators who are tasked with seeking to find ways to translate this science into advice that people can act upon today. However, if society must wait for the science to provide 100% conclusive evidence before anyone ever takes action, how many lives could have been saved in the interim? Therefore, we advocate a two-pronged approach to translating scientific findings regarding environmental exposures and breast cancer prevention: a bottom-up approach—focused on informing the lay public and individuals, while simultaneously performing a top-down approach—focused on influencing policymakers. The current perspective analyzes the strengths and weaknesses to both of these approaches, and encourages scientists to work closely with health communicators to develop theoretically-driven strategies to drive positive changes over time.

Intergenerational transmission of trauma effects: putative role of epigenetic mechanisms

This paper reviews the research evidence concerning the intergenerational transmission of trauma effects and the possible role of epigenetic mechanisms in this transmission. Two broad categories of epigenetically mediated effects are highlighted. The first involves developmentally programmed effects. These can result from the influence of the offspring's early environmental exposures, including postnatal maternal care as well as in utero exposure reflecting maternal stress during pregnancy. The second includes epigenetic changes associated with a preconception trauma in parents that may affect the germline, and impact fetoplacental interactions. Several factors, such as sex-specific epigenetic effects following trauma exposure and parental developmental stage at the time of exposure, explain different effects of maternal and paternal trauma. The most compelling work to date has been done in animal models, where the opportunity for controlled designs enables clear interpretations of transmissible effects. Given the paucity of human studies and the methodological challenges in conducting such studies, it is not possible to attribute intergenerational effects in humans to a single set of biological or other determinants at this time. Elucidating the role of epigenetic mechanisms in intergenerational effects through prospective, multi-generational studies may ultimately yield a cogent understanding of how individual, cultural and societal experiences permeate our biology.

Cultural trauma and epigenetic inheritance

The question of whether and how the effects of cultural trauma can be transmitted intergenerationally from parents to offspring, or even to later generations, has evoked interest and controversy in academic and popular forums. Recent methodological advances have spurred investigations of potential epigenetic mechanisms for this inheritance, representing an exciting area of emergent research. Epigenetics has been described as the means through which environmental influences “get under the skin,” directing transcriptional activity and influencing the expression or suppression of genes. Over the past decade, this complex environment–biology interface has shown increasing promise as a potential pathway for the intergenerational transmission of the effects of trauma. This article reviews challenges facing research on cultural trauma, biological findings in trauma and posttraumatic stress disorder, and putative epigenetic mechanisms for transmission of trauma effects, including through social, intrauterine, and gametic pathways. Implications for transmission of cultural trauma effects are discussed, focused on the relevance of cultural narratives and the possibilities of resilience and adaptivity.