USC researchers are applying tools from the study of epigenetics and social work to discern whether young adults who were abused or neglected as children have more mental health symptoms during the COVID-19 pandemic than those who were not. The result could increase understanding of who is at greater risk in the context of the pandemic and who may benefit most from enhanced and targeted interventions.

A new USC Zumberge grant for faculty at the USC Suzanne Dworak-Peck School of Social Work and Keck School of Medicine at USC aims to make use of an ongoing longitudinal study into the effects of maltreatment on adolescent development along with an epigenetic process called DNA methylation (DNAm) that regulates gene expression. The goal is to help researchers understand the powerful effect of environment on later mental health, and vulnerability to extreme stressors such as the COVID-19 pandemic.

Linking environment and biology

“It’s clear that social experience gets under our skin and impacts mental health,” said Daniel Hackman, assistant professor at the USC Suzanne Dworak-Peck School of Social Work and principal investigator of the USC Zumberge grant. He and Ferol Mennen, associate professor of social work and co-principal investigator, and their fellow researchers hope to shed light on how those early experiences predict increased stress, mental health symptoms and family conflict among a sample of young adults during the COVID-19 pandemic.

“DNAm is an extremely valuable tool in helping us understand how adversity gets translated into differences in mental health later in life,” Hackman said. Down the road, greater understanding of these processes may help uncover ways to prevent longer term effects from abuse and neglect.

The research was one of 19 interdisciplinary studies selected in June for seed funding by the USC Office of Research Services through a special solicitation for epidemic and virus-related research. The grant is jointly sponsored by the USC Office of the Provost and the USC Stevens Center for Innovation. Co-investigators are Joshua Millstein, associate professor, and Daniel Weisenberger, associate professor, both of Keck School of Medicine of USC.

Identifying those most vulnerable

The Zumberge grant augments an existing longitudinal study called the Young Adolescent Project and capitalizes on a current Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) research grant using saliva samples collected from that cohort. This four-wave longitudinal study investigates the impact of child abuse and neglect on development. Children were 9-13 years old at enrollment, with two annual follow-ups and a fourth an average of 7.2 years after enrollment. The study included saliva samples and a comprehensive battery of psychosocial measures at all waves.

In this new study, researchers will collect new data on stress, mental health, and family conflict during the pandemic. The previous data collected will enable researchers to capture a clear snapshot of the effects of the COVID-19 pandemic on a group of young adults from the same communities, comparing those who were abused and maltreated as children with those who were not.

Understanding the lingering effects of abuse and neglect are key to helping find solutions for future generations.

“We know that victims of child abuse and neglect have higher rates of physical and mental health problems throughout their lives. While we know that this adversity can have long-lasting effects, we also know that the environment after adversity relates to the outcome,” said Mennen. 

For example, factors such as sympathetic family members around the victim and opportunities for appropriate intervention and societal supports can remediate some of those effects, Mennen said.

Research like this will help inform policy and practices related to how we as a society respond to victims of abuse or neglect. In addition, she said, “the DNAm may help us understand more about why some who have been abused and neglected as children have easier recovery than others.”

The importance of DNAm

While the same genes are shared by all cells in a person’s body, different ones are active or silent in different cells. Evidence is growing that experiences later in life such as trauma or illness can cause cells to silence a gene or increase its activity. Once these changes occur, they are persistent and are passed on to newly created cells after cell division.

One way this may happen is through DNAm, an epigenetic process that can regulate gene expression. It has emerged as a potential mechanism through which our genes can capture the effects of environmental exposures and spread their influence throughout our bodies. DNAm marks can be used as biomarkers for disease as a readout of the affected biology.

In particular, differences in DNAm may contribute to persistent risk for mental health problems. Researchers typically find DNAm in saliva or blood. Now they will collect these samples during the COVID-19 pandemic and apply for additional funding to analyze those samples, aiming to examine potential long-term effects of the pandemic’s impact that may extend over time.

“This research team is uniquely positioned to identify DNAm alterations as a result of child maltreatment and mental health. Technologically speaking, we will be able to quantify DNAm levels across the human genome for a large number of individuals, with the ultimate goal of improving the lives of affected individuals,” said Weisenberger.

One of the many contributions of the Young Adolescent Project was to document the relationship between child maltreatment and stress response systems, and cortisol reactivity in particular.  As part of that work, saliva samples were collected at four different times during the project.

In the larger research project grant from the National Institute of Health led by Mennen and research scientist Sonya Negriff of Kaiser Permanente Southern California, the team is examining the relationship between child maltreatment and patterns of DNA methylation over development that are derived from those saliva samples, and how those patterns shed light on how mental health problems related to maltreatment emerge and change across adolescence. 

Continuation of groundbreaking work

For Mennen, the project is a meaningful continuation of important work she began nearly two decades prior and a way to honor the memory of her colleague, Penelope Trickett. Trickett, who died in 2016, was a professor of social work and psychology at the USC Suzanne Dworak-Peck School of Social Work known for her groundbreaking research on the psychobiological impact of familial sexual abuse on female adolescents and young adults. Trickett was the principal investigator on the original Young Adolescent Project study, with Mennen serving as co-investigator and Negriff contributing as a doctoral student.

“We’re carrying on Dr. Trickett’s work, which we know she wanted,” Mennen said.

This is the first known study that will be able to address potentially hidden vulnerabilities to the effects of the COVID-19 pandemic, to determine if child maltreatment and DNAm in adolescence are associated with increased stress, mental health problems, and family conflict during the pandemic. This will provide critical evidence to guide the use of resources and target interventions to support families now and to prevent longer-term consequences.

“The more we know about how child maltreatment is related to later outcomes, particularly in the face of the COVID-19 pandemic, the better able we are to prevent and address its effects,” said Hackman.