A family body : We inherit and re-experience, stress, emotions and trauma in our cells : part two

Here is the continuation of information from Chapter 2 of Mark Wolynn’s book It Didn’t Start With You from a previous post :

The most common epigenetic tag is DNA methylation, a process that blocks proteins from attaching to a gene, suppressing its expression.  DNA methylation can positively or adversely affect our health by locking “helpful” or “unhelpful” genes in the “off” position.  When a stressor or trauma occurs, researchers have observed irregularities in DNA methylation that can be transmitted, along with a predisposition for physical or emotional health challenges, to subsequent generations.

Another epigenetic mechanism that plays a significant role in gene regulation is the small noncoding RNA molecule called microRNA.   As with DNA methylation, stess-induced irregularities in microRNA levels can affect how genes are expressed in multiple generations.

Among the numerous genes affected by stress are the CRF1 (corticotropin-releasing hormone receptor) and CRF2 genes.  Increased levels of these genes have been observed in people who have depression and anxiety. The CRF1 and CRF2 genes can be inherited from stressed mothers who share similar increased amounts.  Scientists have documented numerous other genes that can also be affected by trauma experienced early in one’s lifetime.

“Our research demonstrates (that) genes…. retain some memory of their past experiences” (research scientist Uni of Cambridge)

The historic study conducted by Yehuda in 2005 brought considerable awareness to the idea that stress patterns do, in fact, transfer from pregnant women to their children.  Pregnant woman (in their second or third trimester) who were either at or near the World Trade Center during the 9/11 attacks in New York City, and who went on to develop PTSD, delivered children who had low levels of cortisol  Their children also exhibited increased distress in response to new stimuli.  When cortisol levels are compromised, so is our ability to regulate emotions and manage stress.  These babies were also smaller for their gestational age.  Yehuda and her team suggest that the results of the 9/11 study are most likely due to epigenetic mechanisms; they found sixteen genes that expressed differently in those who developed PTSD after 9/11 compared with those who did not.

(Similar studies of Holocaust survivors and their children showed)… epigenetic tags on the very same part of the gene in both parent and child  They compared the results with Jewish families who were living outside of Europe during the war and determined that the gene changes in the children could be attributed only to the trauma that the parents experienced.

.. signficant studies demonstrate… how the traumatic experiences of parents can influence the gene expression and stress patterns of their children.  … Pregnant mothers who developed PTSD gave birth to children who not only had compromised cortisol levels, but also were more easily disrupted by loud noises and unfamiliar people.  One study in England found that children’s emotional and behavioural problems doubled when their mothers were  anxious during pregnancy.

“Trauma has the power to reach out from the past and claim new victims,” writes addiction psychiatrist Dr. David Sack in Psychology Today.  “Children of a parent struggling with PTSD can sometimes develop their own PTSD, called secondary PTSD.”  He reports that about 30 percent of kinds with a parent who served in Iraq or Afghanistan and developed PTSD struggled with similar symptoms.  “The parent’s trauma.. becomes the child’s own and (the child’s) behavioral and emotional issues can mirror those of the parent.”  Children with a parent who was traumatised during the Cambodian genocide, for instance, tend to suffer from depression and anxiety.  Similarly, children of Australian Vietnam War veterans have higher rates of suicide that the general population.

Native American youths on reservations have the highest suicide rate in the Western Hemisphere.  In some parts of the country, the rate is ten to nineteen times higher than that of other American youth  (I would add here that this pattern also occurs in Aboriginal Australian youth).  Albert Bender, a Cherokee historian and attorney specialising in Native American law, suggests that the “intergenerational trauma felt by Native people, but particularly by Indian youth is the result of the historical policy of genocide exemplified by the endless massacres, the forced removals and military campaigns that continued to the end of the 19th century, culminating in the Wounded Knee Massacre.”  He believes generational grief is fuelling these suicides.  “All of these memories,” he says. “resonate in the minds of our young people in one form or another.” He reports that young people are hanging themselves at such a high rate that “a week without suicide is now considered a blessing on many reservations.”

LeManuael “Lee” Bitsoi, a Navajo PhD research associate in genetics at Harvard University, corroborates Bender’s claim that young people are reliving the past in their symptoms.   He believes that epigenetic research is finally beginning to provide substantial evidence that inter-generational trauma is a real phenomenon.

Native American youths, like children of war veterans, like the children of Holocaust survivors, like the children of Cambodian genocide survivors, and like the children of the World Trade Centre attack survivors, are among the modern world’s newest victims of trans-generational trauma.  Alarmingly, the list keeps expanding, Violence, war and a oppressions continue to sow the seeds of generational reliving, as survivors unknowingly transmit what they have experienced to successive generations.

Yehuda claims that the children of PTSD stricken mothers are three times more likely to be diagnosed with PTSD than the children in her control groups.  She also finds that children of survivors are three to four times more likely to struggle with depression and anxiety, or engage in substance abuse, when either parent suffered from PTSD.  Yehuda and her team have been able to distinguish differences in a child’s symptoms based on whether the mother or father passed on the PTSD.  Paternal PTSD… increases the likelihood that the child will feel “disconnected from his or her memories,” and would be more prone to depression or chronic stress responses, whereas maternal PTSD increases the likelihood that a child will have difficulty calming down….. mothers who survived the Holocaust feared being separated from their children, and (the) Holocaust offspring often complained that their mothers were over attached to them.

PTSD experienced by a grandparent can also affect succeeding generations.  As we saw with Gretchen, war related trauma can continue to spiral, affecting the grandchildren of those who suffered the original trauma.

Traumas, not only from war, but from any event significant enough to disrupt the emotional equilibrium in our family – a crime, a suicide, an early death, a sudden or unexpected loss – can lead to our reliving trauma symptoms from the past.  Sacks writes, “Trauma travels through our society, as well as generationally. ”

To be continued:  The next portion and post will concern how being separated from our mothers can affect gene expression of both brain chemistry and stress reponses.