Larry Brendtro, PhD
Dean, Starr Global Learning Network
Co-author, Deep Brain Learning
As a young student in 1960, my science teacher was euphoric in claiming that the discovery of DNA was the most remarkable finding in the history of biology. DNA makes up the chromosomes we inherit from our parents which contain genetic information to build a brand new kid.
For the past half century, the prevailing dogma has been that genes are destiny. Yet only 5% of our DNA contains genes, and the rest was ignored as “junk DNA.” Whoops! It turns out that some of this “junk” determines whether genes are put into play or remain on the sideline. This new discovery is called epigenetics. Epigenetics is the science of how the environment shapes our genes! The prefix “epi” means “on top of” and epigenetics is the study of how life events turn genes on or off. This is a big deal since all of our 20 some thousand genes are located in every body cell, and half influence the human brain.
If genes were destiny, we would be locked in robot mode. Instead, our “designer genes” (excuse the fashion metaphor) can be stitched into silence by tightly wrapped chemical threads, or unraveled so they can do their thing. Ordinarily, this makes children more resilient if raised in a safe, nurturing environment. But everything from toxic chemicals to trauma and poverty can create undesirable epigenetic changes. This also can include the diet and stress level of the mother during pregnancy, and the patterns of child care and education which children receive. To repeat, environment shapes genes.
A dozen years ago, pioneering epigenetics researcher Michael Meaney of McGill University showed that nurturing care-giving turns on genes in the brain that regulate stress; offspring become less anxious and more confident and resilient in facing challenging situations. But neglect and maltreatment impair the brain’s ability to manage stress and regulate emotions. This pattern is shown in research on animals as well as in children who have experienced abuse or maltreatment.
Epigenetics is a dance between genes and environment, and children with different temperaments respond differently. For example, a large study in the UK showed that temperamentally timid school children who were bullied were more likely to become emotionally disturbed than their temperamentally bold peers. None of these correlations are absolute, for if children have warm and supportive relationships, most can thrive in the face of adversity: we have resilient brains.
However, any environmental events beyond the norm of what human brains are designed to handle can create negative epigenetic effects. For example, there are thousands of potentially toxic chemicals in the environment which may be producing epigenetic aberrations seen in high rates of autism, ADHD, and bi-polar disorder. Even the drugs prescribed for emotional problems may turn out to be epigenetically toxic, a warning Big Pharma refuses to list on medication labels.
Nutrition can also alter gene expression. For example, during a World War II famine in Holland, pregnant women gave birth to down-sized babies whose growth genes were epigenetically redesigned so they could survive on very few calories. The bad news: once the war was over, normal diets made them obese. Most epigenetic effects are reset by later changes in environment or at reproduction. But sometimes, as in the Holland famine, the epigenetic changes persisted in several generations of offspring born small and at risk for obesity.
We now know that some adverse life experiences can cause epigenetic anomalies that may be passed on for up to four generations (Carey, 2012). Thus, violent oppression of your great-grandparent may cause you to inherit epigenetic ill effects, even though you never experienced this abuse. This is likely related to the health problems common to aboriginal peoples worldwide who had their culture decimated by colonial enslavement.
The good news is that unlike genes which are fixed, epigenetics is caused by the environment, and environments can be changed. For millennia, children thrived in cultures that met universal growth needs for Belonging, Mastery, Independence, and Generosity. These Circle of Courage needs are mapped into brain programs as Martin Mitchell and I explain in our book Deep Brain Learning.
Hear more from Dr. Brendtro about the new and exciting discoveries in Deep Brain Learning that affect our work with at-risk youth. Our February webinar, "Designer Genes: New Frontiers in Deep Brain Learning" will be broadcast live on February 27 at 10 a.m. Pacific/1 p.m. Eastern Time. Can't make the live? The recording will be available on demand for 14 days following the event.