Do Epigenetics Affect Mental Health?

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Summary: Yes, epigenetics do affect mental health. Reporting on the potential causes of mental health disorders typically focuses on two general areas: genetics and environment. However, there’s another factor that isn’t as widely known among the general public, which may have a significant impact on determining a person’s risk for mental illness: epigenetics.

Key Points:

Epigenetics is a term coined by an embryologist named Conrad Waddington in 1942.
Interest in the impact of epigenetic on mental health has gained increased attention in recent years.
While genetics – in most cases – refers to the expression of the DNA we inherited from our parents, epigenetics refers to changes in our genes caused by our individual experiences after birth.
Epigenetics can help us understand not only our initial genetic predisposition for developing mental health disorders, but how the current state of our genes and genetic expression increase or decrease risk of developing mental health disorders.

Epigenetics: Origin of the Concept and Basic Facts

When Waddington coined the word epigenetics, he was describing the intricate biological processes through which a single fertilized egg transforms into a complex organism that contains myriad different cells, tissues, and organs.

Much like the complicated transformation that Waddington tried to define, the meaning of epigenetics has changed significantly since he first used it in 1942.

Today, as social worker Krystal Kavita Jagoo, MSW, RSW, explained in a July 2023 article, epigenetics is “…the study of how genes may be affected by the experiences people have, which can then be passed down to future generations.”

In other words, instead of viewing internal and external factors as separate influences, epigenetics explores the way individual experience can alter genetic expression.

For members of certain populations (such as historically oppressed or systemically abused groups), epigenetics can also explain how events that occurred long before they were born conceived can affect their health today.

Mental Health and Epigenetics: Are They Related?

The authors of an October 2016 article in the journal Neuroscientist described the relationship between epigenetics and mental health in the following way:

“The ultimate goal of epigenetic studies of mental illness is to understand how genetic vulnerabilities interact with an individual’s life experiences to establish stable changes at precise genomic loci, which then control the levels of gene expression or inducibility.

Together, this linking of genes and environment through epigenetic mechanisms determines that individual’s vulnerability to psychiatric syndromes over a lifetime.”

In the July 2023 article cited in the previous section, nurse practitioner and instructor Deidra Thompson, DNP, explained that actions and experiences can impact genes, which can in turn affect individual vulnerability to certain mental health disorders:

“An individual’s environment and behaviors, including nutrition, exposure to chemicals, exercise, adversity, smoking and stress, can affect gene expression. This expression of genes affects development and disease and can make one more susceptible to mental illness.”

The Epigenetic Impact of Childhood Trauma

Epigenetics can also help to explain how adverse childhood experiences (ACEs) can negatively impact individual mental health years or decades later, even if the individual doesn’t remember the original trauma.

An international team of researchers from China and the United States addressed this aspect of epigenetic research in a July 2021 article in the journal Frontiers in Genetics:

“Epigenetic processes may be one way by which early-life stress becomes biologically embedded, altering how children respond physiologically and behaviorally to stress.”

The researchers noted childhood trauma can impact the following systems one a genetic level by:

HPA Axis. The hypothalamic-pituitary-adrenal axis plays a fundamental role in how people perceive and respond to stress.
Monoaminergic transporters or receptors. These are components of the central nervous system (CNS) essential for the transmission of mood-related neurotransmitters such as dopamine, serotonin, and norepinephrine.
Monoamine oxidase. This enzyme controls the reabsorption of dopamine, serotonin, and norepinephrine in the CNS.

The article included references to several prior studies that explored the epigenetic impact of childhood trauma and its relationship to mental health challenges later in life. These studies included the following:

Early life stress plays a role.

A December 2020 study found that early-life stress can cause changes in synaptic plasticity (the ability of neurons to alter the strength of their connection). These changes can, in turn, increase individual risk of anxiety, depression, and diminished cognition.

Social stress plays a role.

A January 2021 study determined that exposure to social stressors early in life can influence the expression of several genes associated with serotonin, which can increase risk of depression later in life.

Trauma plays a role.

A July 2020 paper reported that traumatic experiences early in life may alter the development of genes within the hippocampus and prefrontal cortex, These are areas of the brain that influence functions such as learning, memory, and high-level cognitive processes. The potential effects of these epigenetic changes may include anxiety, low sociability, and impaired memory.

Parental attachment may play a role.

An October 2020 study identified changes in receptors within the prefrontal cortex of rats that were subjected to daily four-hour separations from their mothers for 20 days after their birth. These mice exhibited what the researchers described as “autism-like behavioral deficits.” However, the separation affected neither their learning capacity nor their memory.

With each new study into the epigenetic effects of childhood trauma, researchers more clearly define the mechanism through which ACEs increase the likelihood of mental health challenges during adulthood.

The Multi-Generational Impact of Epigenetic Changes

Individual behaviors and childhood stressors are not the only causes of epigenetic change. As we noted earlier in this post, epigenetics may also be responsible for passing the impact of systemic trauma from one generation to the next.

A May 2022 review in The American Journal of Psychiatry addressed this topic, exploring the impact that structural racism and generational trauma may have on differences in rates of depression between non-Hispanic White people and African America people in the United States.

Highlights of this review included the following insights:

Descendants of victims of mass trauma are more likely to have medical problems such as compromised immune system, impaired endocrine system, and adrenal maladaptation, which can cause disrupted sleep, persistent fatigue, and stress intolerance.
The social impact of mass trauma on later generations includes a greater prevalence of substance misuse, domestic violence, and child maltreatment.
From a psychological perspective, mass trauma is linked with more common or more severe cases of panic disorder, other anxiety disorders, depression, and posttraumatic stress disorder (PTSD).
African American adults who have depression report having more severe, longer lasting, and debilitating symptoms than do White adults.
From 1991-2017, the yearly rate of attempted suicide among African American adolescents increased by 73%. Over the same period, the annual number of attempted suicides by White adolescents decreased by 9%.

According to the research team, structural racism, such as housing discrimination, insufficient access to mental health treatment, cumulative trauma, such as exposure to hate crimes, parental incarceration, and elevated levels of ACEs, should be thought of as follows:

“[They are] fundamental drivers of the intergenerational transmission of depression.”

The researchers also noted that studies of other oppressed groups throughout the world – including First Nation and Native American communities as well as survivors of war and ethnic cleansing efforts in Rwanda, Cambodia, Armenia, and Palestine – yielded similar findings.

Can Epigenetics Improve Mental Health Treatment?

In addition to linking specific genes with specific mental illnesses, epigenetics also casts added attention on behavioral and generational factors.

Continued advances in this field will hopefully improve treatment outcomes by promoting both breakthrough pharmacological solutions and enhanced therapeutic and educational services.

As the authors of the October 2016 Neuroscientist article observed: