The
Ghost in Your Genes is a 50-minute documentary produced by the BBC in 2006
(http://topdocumentaryfilms.com/the-ghost-in-our-genes/).
It elucidates something astonishing about inheritance that counters what we
have been taught in recent years—i.e. that our approximately 30,000 genes
control everything about who we are. Instead, we learn that the lives of some
of our forebears—what they ate, what they breathed, perhaps even what they
saw—can directly affect us years later. In other words, though we get our genes
directly from our parents and grandparents via sperm and egg, we are also
affected by their experiences—which can determine which of our genes are expressed,
and how. The latter is a short version of what is now called
“epigenetics”—changes in the genome that do not involve structural changes or
mutations in the genes themselves, but rather in how existing genes are expressed
and at what level. As Dorothy Roberts explains in her excellent work,
Fatal Invention, where she referred to
The Ghost in Your Genes, “Scientists
call each epigenetic change a
mark,
and the total set of epigenetic marks in an organism are the
epigenome.” Most importantly, the
“epigenome can be modified by the environment,” and those changes can last
beyond a single life. Hence, not only what our grandparents
were genetically, but even what they
experienced can affect us many years
later.
This
is (or was when it was discovered) truly paradigm-shifting stuff, because it
means that the environment, the conditions that we all experience, can be
passed on to our offspring and to their
offspring. If we undergo certain kinds of stress—and scientists have already
done research on the effects on unborn children of parents going through the
horror of Nazi concentration camps, the collapse of the Twin Towers on 9/11,
the effects of famines and pesticides—those stressors can affect our unborn
heirs years later. We are not born with a blank slate of genes, protected from
outside influence in their cozy DNA packets, as scientists once thought. We are
also born with the experiences of generations that preceded us, experiences
that can, and often do, leave their epigenetic marks. And if those who commit
atrocities such as the bombings of Hiroshima and Nagasaki or the 400-year
horror that was slavery and then Jim Crow and now mass incarceration in the
allegedly free and equal United States of America—if they think that their evil
is visited only upon those who directly experience it, then they must think
again. For epigenetics is now telling us that the effects of evil (and good)
actions are passed on to the generations.
The Ghost in Your Genes starts out with
the insight of a mild-mannered, and very appealing (he actually came near tears
when explaining some of his discoveries) British geneticist named Marcus
Pembrey, who noticed something strange in his work with children. He noticed
that a rare genetic disorder, known to be caused by a deletion in a specific chromosome
(#15), expressed itself differently depending on whether the gene came from the
father or the mother. If the father passed the deletion on, the child was
afflicted with Prada villi syndrome—a condition marked by severe overweight. If
the mother passed it on, the child was afflicted with Angelman’s syndrome, a
condition where children lack speech but seem exceptionally happy. Pembrey was
shocked by this: the exact same genetic deletion resulted in two wildly
different expressions in the human body. In the documentary, Pembrey says, “It was as if the genes knew where they came
from.” This was unprecedented and altogether unexpected. Pembrey wrote up
his results and published them, but received little response. Until one day he
received an email from a researcher, Oluv Bygren, doing work in a remote town
in Sweden near the Arctic Circle, which had the peculiarity that its archives recorded
not only births and deaths, but also conditions in the lives of the people
involved, particularly relating to the harvests. This was because being so
remote, the harvests were critical: too little grain and there would be famine.
Pembrey and Bygren subsequently were able to match the records of the recurring
famines that occurred due to natural climate fluctuations with the deaths of
inhabitants—specifically death from diabetes. To their great joy as scientists,
they were able to plot the births during famines with records of death from
diabetes, to find almost perfect matches over the years. In other words, if a
woman gave birth during a famine year, her child would be more likely to later suffer
from diabetes, and so would her grandchildren. The change in the expression of
genes from an environmental event was passing on to subsequent generations. Prof.
Michael Skinner, another researcher from the state of Washington, comments as
follows:
What
this means is: an environmental exposure that your grandmother had could cause
a disease in you, even though you never were exposed to the toxin, and you will
pass it on to your grandchildren. You are directly affected by the stress your
grandmother experienced.
Again, this is astonishing stuff in
light of the standard view of genetic inheritance, which says that genes pass
untouched (except by mutation) from one generation to another; they are protected, essentially unaffected
by our experience as individuals. But now, we must consider the contrary view
that what we experience is, or can be passed on to not just one but several
succeeding generations, to our biological heirs.
Dr.
Michael Pembrey calls this “genomic imprinting.” Genomic imprinting means that
genes have a memory of where they came from—in the cases he first discovered,
whether the gene deletion on chromosome #15 came from the mother or the father.
This is one answer to the question sought by the researchers in the
documentary: if the activity of genes is controlled by a switch, and if this
switch controls the critical decision of whether a given gene is turned on or
off—then what turns such genes on or off?
To further answer this, the documentary shifts to a couple, the Mullins’, who after
many years without a child turned to in vitro fertilization. It was successful
and resulted in the birth of their first son, Keiran. But Keiran, even in the
womb, showed signs that something was amiss: he displayed symptoms of something
called Beckwith-Wiedemann syndrome. Such children tend to be very large, have
protruding tongues, and have a tendency to develop cancerous tumors. It turned
out that Keiran did have the
syndrome, had several operations to fix some of the problems, and underwent recurring
examinations for cancer. But the question was, what might have caused the
disease? Another researcher named Wolf Reik came up with the answer, derived
from his work with lab mice. Reik noticed that placing mouse embryos in a
culture dish for a short time tended to affect the gene switch. He researched
the records of babies with Beckwith Wiedemann’s and found the correlation:
those who had been fertilized with IVF were 3 to 4 times more likely to have
the syndrome. Something about altering the environment—having the embryo or the
egg outside the womb—was causing an epigenetic change leading to the syndrome.
Moreover, Reik found from experiments that mice with environmentally-altered
gene switches also passed the condition on to several subsequent generations.
Reik’s comment: “A simple environmental event could affect the way genes
worked, and it could be passed on.”
There
is more to this splendidly informative documentary—including research on births
to women pregnant during 9/11, indicating the affects of major stress on their offspring—so
I recommend that anyone with even the slightest interest in the subject should
watch it. What I would feel remiss in not mentioning, though, is one more
episode, of lab research done by Dr. Michael Skinner of Washington. Skinner
exposed pregnant rats to large doses of pesticides commonly used on our crops.
Not unexpectedly, 85% of the exposed rats displayed symptoms of tumors, kidney
damage, and immune dysfunction. What was unexpected was that after the third
generation, the rats’ offspring showed the same degree of toxic effects: 85% of
the third generation individuals were affected by tumors, kidney damage, and
immune dysfunction! This was a new phenomenon in Skinner’s experience: an
environmental toxin affecting not just
the individual exposed, but extending its effects to several subsequent generations.
The voice-over narrative made the point: “the exposure of a single animal to a
toxin was causing a whole range of diseases in almost every individual of the
following generations.” And Skinner himself
generalized as follows: “What your grandmother was exposed to when she was
pregnant could cause a disease in you, even though you had no exposure, and
you’re gonna’ pass it on to your grandchildren.”
For
Dorothy Roberts, and for us, these findings bear critical importance. What they
mean is that the environment in which we live, and the stressors from that
environment, can have direct and long-lasting effects on our bodies. Harvard
biologist and public health expert Nancy Krieger has studied just this, and she
calls it “embodiment:”
“Embodiment to me refers to the many many, many
different ways that we literally incorporate the world outside of us in us, in
the expression of our biology….My focus is on how inequity becomes embodied and
harms health.” (Roberts, p. 130)
Specifically, Krieger has studied
the relationship between environmental stress and birth weight. In a 2004 study
of 352 births, Krieger found that women reporting high levels of racial
discrimination were almost five times (5X) more likely than those reporting no
racial discrimination to deliver low-weight babies, and had three times (3X)
the risk of preterm birth. In other words, stress leads to low birth weight,
and low birth weight is often a predictor of such later-occurring maladies as
diabetes, cardiovascular disease, and immune system dysfunction. This is the key point that Dorothy Roberts
emphasizes again and again: “Epigenetics
may masquerade as genetic difference, but its biological effects stem from the
environment, not mutations of the genetic code.” The new racism cloaked in
the “objectivity” of science often, wittingly or not, takes part in this
“masquerade.” Characteristics that have long been touted as an unalterable
product of genetic difference—that is, the consequence of being born a certain race—are actually more often a product
of the environment, which is to say,
of society and the practices it dictates for the people it governs. It is a
product of how people are treated—of what place they are allowed to occupy in a
given society, of what access to that society’s goods they are allowed to have.
And that treatment—particularly if it involves frequent humiliation and
stress—affects not just them, but their offspring for generations and
generations to come. When we reflect that even a single stressful event—such as
9/11—can affect generations of offspring, imagine what a lifetime or several
lifetimes of stressors can do to a people’s epigenetic genome, to the way its genes
are expressed.
The
good news, of course, is that environments can change. Societies can wake up to
the burdens they are imposing on some classes of people. The only question is
whether, and to what degree, a given society wishes to change, or if it wishes
to perpetuate the epigenetic condemnation it imposes on its victims and their
heirs in perpetuity.
Lawrence DiStasi
addendum, 8.16.13: A recent study
at UCLA’s Cousins Center for Psychoneuroimmunology (see
www.biosciencetechnology.com) provides
a fascinating gloss on the above discussion. Steven Cole and others, after many
years studying the negative effects of stress on gene expression, studied the
positive effects of happiness on gene expression (epigenetics). They studied
two types of happiness: 1) eudaimonic well-being—the kind derived from having a
deep sense of purpose and meaning in life; and 2) hedonic well-being—the kind
that derives from self-gratification and pleasure. Though there is certainly
overlap (both can be exhibited by people with strong social connections, and
the presence of one can influence the other when people who “feel good” find
more meaning in their lives), the differences when measured at the epigenetic
level were striking. People with high levels of eudaimonic happiness displayed highly
favorable gene expression in their immune cells: they had low levels of
inflammatory gene expression, and powerful antiviral and antibody activity.
People with high hedonic happiness, by contrast, had an opposite profile—one exhibiting
high inflammation (the kind that can lead to cardiovascular and other diseases)
and low antiviral and antibody gene expression. This despite the fact that, outwardly,
eudaimonics and hedonics exhibited very little difference in their apparent
emotional well-being.
Professor
Cole concludes that this study has important implications for the age-old
question of what constitutes “the good life”: feeling good, or doing good.
Though on the surface it appears that “feeling good” and “doing good” have the
same effect on most people, at the level of health as measured by gene
expression, they differ quite a bit. “Doing good” leads to a healthy immune
system response, whereas “feeling good” can lead to the opposite. “Apparently,”
says Cole, “the human genome is much more sensitive to different ways of
achieving happiness than are conscious minds.” The genome may also provide a
more “objective approach to moral philosophy rooted in the utility of health
and the basic biology of human nature.”
It
is striking that this initial research displays a remarkable correlation with
the wisdom traditions that have counseled human groups for millennia. As just
one example, the Tibetan Buddhist teacher Matthieu Ricard, in his book on Happiness, advances a very simple and anti-modern formula. Happiness, he says,
stems from serving others rather than from caring predominantly for oneself.
Countless other spiritual teachers have said the same thing. Now, it appears,
the heretofore inscrutable biology of the human genome seems to be supporting
the same wisdom, this time from deep within the workings of the human body.
