What is Epigenetics?

excerpted from the Choice Mom E-guides to Eggs and to Embryos, submitted by Sarah Kowalski

“Within the next 10 to 20 years we will discover that our genetic code only accounts for 10 percent of what gets inherited and what makes us who we are. Genes at birth are not as essential as we once thought.”  — Jorge, neuroscientist

My friend Jorge, and my own training and reading in current biology and neuroscience, is helping me understand that all emotions and thoughts are actually biochemical events in the cells and brain. Emotions create a kind of biochemical soup in our bodies. For my baby-to-be — who was not created from my own eggs or the sperm of someone I loved —  I realized that every time I danced, he would feel my rhythm. Eventually he would hear my joy at singing practice. He’d experience my bliss at Qigong class.

A burgeoning field called ‘fetal origins research’ looks at the effects of stress, diet, pharmaceuticals, chemicals and pollutants on the health of the fetus, at birth, and throughout life.

Conditions in utero play a major role in creating a foundation for health, intelligence and temperament.

Diet and Nutrition

The Dutch Famine Birth Cohort Study (which examined the effects of diet during World War II blockades) showed that when a fetus is malnourished in utero, the baby’s health suffered for its entire lifetime. The effects were different depending on which trimester the malnutrition occurred. The birth weights of children who were well fed at conception, and malnourished in the second and third trimesters were born underweight. In time, they stayed small and had lower obesity rates than the general population. Conversely, babies who were malnourished only during the first trimester were born with a normal body weight, but over time had a greater incidence of obesity and health problems. Even though they seemed healthy at birth, something had happened to their development in the womb.

Prenatal Maternal Illness

Another study looked at the effects of the 1918 flu pandemic in which 550,000 Americans died in four months, but a staggering 25 million people caught the virus and survived. Women of child-bearing age were among the hardest hit by the flu. An economist named Douglas Almond studied census data of children who were in utero while their mothers had the flu. The children were 20 percent more likely to have heart disease or be disabled than those not gestated during the flu. They tended to be shorter. They were 15 percent less likely to graduate from high school. The men earned 5-9 percent less. It has become accepted that many diseases, such as cancer and diabetes, have a genetic component that doesn’t mix well with fatty or salty foods and too little exercise. But researchers also are increasingly studying the uterine environment as a critical period of development.

Defining Epigenetics

In the multi-disciplinary field of fetal origins, Epigenetics is a relatively new study of human inheritance. The term refers to long-term alterations of our DNA coding that don’t involve changes to the sequence itself — yet causes variations in gene expression. DNA is not a template that produces identical copies of the same thing. The genes still need instructions for what to do and where to do it. For example, at conception, all cells are genetically identical and yet they differentiate into many types of cells to form the heart, lungs, reproductive organs, brains. We now understand that the epigenome refers to the organic molecules (or tags) that adhere to the DNA and tell each cell what genes to turn on and off in order to form its structure.  Changes in environment — including in utero — cause different amounts of chemicals to adhere to the genes, which alter the behavior of the gene.

Epigenetics is the study of these gene-regulating chemical attachments.

A revealing agouti mouse study showed that differences in diet and chemical exposure in utero literally turned the gene for hair color on and off and also correlated to the development of certain diseases. The epigenome also explains why identical twins can be far from identical, including developing different diseases. As the twins age, different tags attach to the genomes of each twin.

I read a nice analogy that helped me wrap my brain around this.  The analogy likened DNA to a script that can be interpreted differently. Shakespeare’s Romeo and Juliet has been produced numerous times. They start with the same script, yet produce entirely different productions. The genetic code itself doesn’t change (or mutate). Instead, epigenetic changes — ‘notes in the margins’ — are responsible for the differences.

All of my research has helped me recognize the importance I have in shaping my child in utero, regardless of whether the embryo comes from my genetic material. And the good news — early childhood development (attachment, breast milk) reminds us that our influence as nurturing mothers has lifelong impact. I am writing my own notes in the margins as we go!


Sarah KowalskiAbout Sarah: She became a Choice Mom in 2014. She is a former attorney turned Life Coach who specializes in the mind/body connection. She is writing a memoir about her journey that includes spiritual life lessons and how-to details. She coaches women who are struggling with the decision to become a Choice Mom, are facing fertility issues, or are considering egg donation in the U.S. or abroad. She works in-person in the Bay Area, as well as on Skype, and is organizing online and in-person support groups for 1) women considering egg donation, and 2) women who are traveling abroad for IVF treatment. sarah@choicemamababyproject.com


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