The real danger of separating children from parents is not the
psychological stress – it’s the biological time bomb. The screaming and
crying, the anguish and desolation is gut-wrenching. But the fallout
pales in comparison to the less visible long-term effects that are more
sinister and dangerous.
Separating children from their parents, in a strange land, among
strangers, causes the most extreme life stress a child can experience.
And it causes profound and irreversible changes in how their DNA is
packaged and which genes are turned on and off in the cells of the body,
in organs like the pancreas, the lungs, heart and brain – leading to
lifelong changes in its structure and function.
I am the director of the Lieber Institute for Brain Development and
the Maltz Research Laboratories at the Johns Hopkins University School
of Medicine, where scientists study how genes and the environment shape
the development of the human brain.
Our studies and those of many other researchers around the world have shown that early life stress alters how DNA is packaged, which makes cells function differently than their original mandate.
How DNA is packaged alters its function
How DNA, the blueprint of life, is packaged in cells dictates how
cells function. Virtually every cell in the body has the same DNA, as
they are all descendants of that first fertilized egg. But a liver cell
knows it’s not a lung cell, which knows it’s not a brain cell. The way
the cells “know” has to do with how the DNA in cells is packaged, a
process called “epigenetics.”
The DNA double helix is wrapped
around a core of histone proteins that regulate which and when
particular genes are turned on and off.By molekuul_be/shutterstock.com
DNA is organized in a complicated protein package, which acts like
insulation, protecting the DNA strand. This insulation determines which
genes are activated to make the proteins required by a particular cell.
Between the various tissues and organs, the packaging of DNA varies –
like a liver cell versus a lung cell – allowing each cells to have a
unique collection of proteins. Studies of children who have experienced major early childhood stress
reveal that dysfunction in many organs in the body years after the
stressful event, raising the risk of heart disease, lung disease, high
blood pressure, diabetes, poor school performance, drug abuse and mental
illness. Scientists in the institute where I work have recently shown
that the sensitivity of DNA packaging to environmental stress is
greater during the first five years of life than all of the rest of life
combined.
Harry Harlow, a psychologist at the University of Wisconsin,
performed a controversial series of studies in the 1950s on infant
monkeys that were isolated from their mothers for a few months – a
similar situation to the period of separation experienced by young
immigrant children at our borders, which is getting even longer in spite
of the latest policy. Harlow’s infant monkeys became profoundly
disturbed for the rest of their lives.
When these monkeys reached adulthood, studies revealed significant
alterations in the structure and chemistry of their brains. Research in
Romanian orphanages focusing on human children reared without parental
support also show significant increases in the frequency of later life
psychological and social disabilities as well as medical illnesses and
changes in the anatomy of the brain.
Perhaps the best-known research on this subject was with children
raised in Romanian orphanages in the 1980s and 1990s. In their
compelling book “Romania’s Abandoned Children: Deprivation, Brain Development, and the Struggle for Recovery,” Nathan Fox of the University of Maryland, Charles Nelson of Harvard and Charles Zeanah of Tulane
document the devastating impact of institutions on infants who are
deprived of their parents’ emotional support. In addition to profound
behavioral and intellectual problems, the brains of these children
showed diminished growth a decade later.
How stress turns cells from Jekyll to Hyde
How does stress do these things? We know that stress causes a biological reaction in the body, including increasing the quantity of cortisol,
the so-called “stress hormone.” But it also increases the production of
several inflammation-related proteins. In cases of infection, these inflammatory proteins are sentinels that help protect the body against infectious agents. But in the absence of infection, they can damage the host.
They do this by getting into cells and changing the packaging of DNA.
Forced separation from one’s parents especially in unfamiliar
circumstances is an extreme form of childhood stress that causes stress
hormones to alter DNA packaging, transforming the behavior of the cell.
Some of how the DNA is repackaged is permanent,
and the cells involved go through life in an altered state, making them
hypersusceptible to a myriad of other stresses and medical problems.
Scientists know how dangerous toxic stress
– severe, prolonged or repetitive adversity with a lack of the adequate
adult support – is to children because they know how it damages and
modifies the DNA in their cells. Now you know too. The longer the
authorities fail to get these children reunited with their parents, the
more responsible we are as a country for violating their DNA and causing
a lifetime of psychological and physical disease
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