With Mother’s Day coming up, it can be fun to talk about some of our family’s genetic traits, like eye color, hair color, or having mid-digit hair (yup, that’s genetic too!). We all know that we get our genetics — the basic blueprints that make us who we are — from Mom and Dad, but it turns out that how they lived their lives before we were conceived affects who we are as well. Specifically, it’s been recently shown that a parent’s epigenetics — in addition to their genetics — get passed on to their offspring. What does this mean exactly, and what are the implications?
While our genetics are a collection of our genes (together making up our genome), epigenetics are certain factors that control which genes we’re using. And according to two recent studies, because of epigenetics, what your mother ate before you were even conceived, and whether your father had a stressful childhood or not, may affect who you are today.
In mid-April, a study was published showing that mice that were stressed when they were young not only grew up to be greater risk-takers — being more likely to go out into wide-open spaces than normal mice — but their children had the same behaviors. In other words, the stressful childhood of the parents led to adult behaviors that were passed on to their offspring. The researchers found out that this was due to inheriting specific microRNAs (miRNAs) in the sperm of the father animals that are likely involved in regulating epigenetic processes. But it’s still unclear how exactly the miRNAs are changing the epigenetics, and how the epigenetic modifications are leading to the less risk-averse behaviors.
Similarly, just last week — in time for Mother’s Day — a study was published showing that what Mom eats right before conceiving a child, and early during the pregnancy, can affect what that child is like when they grow up, and this is again probably due to epigenetics. Specifically, the investigation studied 167 women in rural Gambia (a country in West Africa), where seasons significantly affect their diet and nutrition intake. Basically, it was found that these seasonal variations cause women to have seasonal epigenetic changes, and this influences the amounts of different biomarkers in the women before and during early pregnancy, which affects the epigenetics of their children. However, unlike the study done in mice, in this study it was unclear in what ways the epigenetic changes affect how the offspring look and behave. So, in addition to folic acid being an important nutritional supplement for women to take before conceiving and early during pregnancy, it looks like there are other key nutritional factors that we have yet to understand.
Clearly, our lifestyle before having children affects what they’ll be like. Although we have much to learn about how this works exactly, knowing that it is a real factor may make young people (who plan on having kids someday) want to more closely evaluate their lifestyle choices, from voluntarily being in a stressful environment to what kinds of foods they regularly eat, even long before meeting that special somebody.
For further reading:
- Katharina Gapp et al.’s article “Implication of sperm RNAs in transgenerational inheritance of the effects of early trauma in mice” in Nature Neuroscience
- Paula Dominguez-Salas et al.’s article “Maternal nutrition at conception modulates DNA methylation of human metastable epialleles” in Nature Communications
- Jeffrey M. Perkel’s article “Traces of Trauma in Sperm RNA“
- Emily Willingham’s article “Epigenetic Effects of Mom’s Diet“
- Teisha J. Rowland’s book Biology Bytes: Digestible Essays on Stem Cells and Modern Medicine