“Epigenetics” is an emerging area of scientific research that shows how environmental influences—children’s experiences -actually affect the expression of their genes. The body turns genes on and off depending on the early environmental experiences. Genes are not fixed – they are malleable and changed through the interaction with the environment.
Epigenetics is the study of how cells control gene activity without changing the DNA sequence. Epigenetic changes are modifications to DNA that regulate whether genes are turned on or off. These modifications are attached to DNA and do not change the sequence of DNA building blocks.
Because epigenetic changes help determine whether genes are turned on or off, they influence the production of proteins in cells. This regulation helps ensure that each cell produces only proteins that are necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Patterns of epigenetic modification vary among individuals, in different tissues within an individual, and even in different cells within a tissue. Environmental influences, such as a person’s diet and exposure to pollutants, can impact the epigenome.
Nature versus nurture – the age-old debate
The old ideas that genes are “set in stone” or that they alone determine development have been disproven. Nature vs. Nurture is no longer a debate—it’s nearly always both!
Epigenetics explains how early experiences can have lifelong impacts
When experiences during development rearrange the epigenetic marks that govern gene expression, they can change whether and how genes release the information they carry.
Thus, while genetic factors exert potent influences, environmental factors have the ability to alter the genes that were inherited.
Thus, the epigenome can be affected by positive experiences, such as supportive relationships and opportunities for learning, or negative influences, such as environmental toxins or stressful life circumstances, which leave a unique epigenetic “signature” on the genes. These signatures can be temporary or permanent and both types affect how easily the genes are switched on or off. Recent research demonstrates that there may be ways to reverse certain negative changes and restore healthy functioning. But the very best strategy is to support responsive relationships and reduce stress to build strong brains from the beginning.
Another consideration is a prenatal vitamin for men, adding extra nutrients can only help when it comes to pregnancy and a strong healthy baby.
Young brains are sensitive to changes in the way their genes react to the environment. That’s why it’s crucial to provide a safe and nurturing environment for a developing child. Childhood experiences rearrange the way their genes turn on and off . The DNA that makes up our genes accumulates a specific chemical ‘cocktail’ that directly affects the way a child’s body and nervous system interact with the world around them. Some chemical cocktails work more favourably and assist a child to make the most of their lives.
Epigenetics and trauma
Although frequently misunderstood, adverse fetal and early childhood experiences can—and do—lead to physical and chemical changes in the brain that can last a lifetime.
Injurious experiences, such as malnutrition, exposure to chemical toxins or drugs, and toxic stress before birth or in early childhood are not “forgotten,” but rather are built into the architecture of the developing brain through the epigenome. The “biological memories” associated with these epigenetic changes can affect multiple organ systems and increase the risk not only for poor physical and mental health outcomes but also for impairments in future learning capacity and behavior.
Real-life example of epigenetics – The Dutch Famine study
The Dutch famine of 1944–1945, known in the Netherlands as the Hongerwinter (literal translation: hunger winter), was a famine that took place in the German-occupied Netherlands, especially in the densely populated western provinces north of the great rivers, during the winter of 1944–1945, near the end of World War II.
A German blockade cut off food and fuel shipments from farm towns. Some 4.5 million were affected and survived thanks to soup kitchens. At least 22,000 deaths occurred due to the famine.
The Dutch Hunger Winter has proved unique in unexpected ways. Because it started and ended so abruptly, it has served as an unplanned experiment in human health. Pregnant women, it turns out, were uniquely vulnerable, and the children they gave birth to have been influenced by famine throughout their lives.
They found that the people who had been in utero during the famine — known as the Dutch Hunger Winter cohort — died at a higher rate than people born before or afterward. “We found a 10 percent increase in mortality after 68 years,” said Dr. Lumey.
The Dutch Famine Birth Cohort Study found that the children of pregnant women exposed to famine were more susceptible to diabetes, obesity, cardiovascular disease, microalbuminuria and other health problems.
Moreover, the children of the women who were pregnant during the famine were smaller, as expected. However, surprisingly, when these children grew up and had children those children were thought to also be smaller than average. This data suggested that the famine experienced by the mothers caused some kind of epigenetic changes that were passed down to the next generation. Despite this, a subsequent study by the same author failed to find a correlation between maternal exposure to famine and birth weight of the next generation. Nonetheless, the significance of prenatal physical therapy and general care cannot be undermined.
The patterns that Dr. Lumey and his colleagues documented are not disputed, but scientists still are struggling to understand how they come about.
“How on earth can your body remember the environment it was exposed to in the womb — and remember that decades later?” wondered Bas Heijmans, a geneticist at Leiden University Medical Center in the Netherlands.
Dr. Heijmans, Dr. Lumey and their colleagues published a possible answer, or part of one, on Wednesday in the journal Science Advances. Their study suggests that the Dutch Hunger Winter silenced certain genes in unborn children — and that they’ve stayed quiet ever since.
But scientists have learned that later experiences — say, exposure to a virus — can cause cells to quiet a gene or boost its activity, sometimes permanently.
The study of this long-term gene control is called epigenetics. Researchers have identified molecules that cells use to program DNA, but how those tools work isn’t entirely clear.
Prenatal conditions can influence people’s health across their lifetime
So here’s the theory on the Dutch Famine consequences:
Perhaps the Dutch Hunger Winter added a methyl group (a specific expression of DNA) to fetuses born to starving mothers, which made the PIM3 gene less active — and continued to do so for life. Although, it’s possible that the survivors had some genetic variant that made them resilient and gave them a distinctive epigenetic profile not captured in this study.
John M. Greally, the director of the Center for Epigenomics at Albert Einstein College of Medicine, postulated that maybe the Dutch famine made some types of cells more common, rather than altering the epigenetics.
If scientists can solve the Dutch Hunger Winter’s lingering mysteries, they might also get some clues to how other kinds of stress can reprogram children’s health even before they’re born.
The questions we have about epigenetics are so complex, and we haven’t gotten to the point yet of being able to see the big picture.