Methylation and Epigenetics
Methylation across generations
What Is Epigenetics?
To help answer this question, let’s use bees as an example to help demonstrate how epigenetics works. The worker bees select for and create a queen bee by feeding her a specialized diet of royal jelly. Royal jelly “turns on” or activates genes in the selected bee and begins the process of changing the bee from a worker bee to a queen bee (1).
The term epigenetics in its broadest sense is a change in gene expression that does not involve actual changes to your DNA. The most common causes of the changes in gene expression are histone modification and DNA methylation. Methylation is the addition of a methyl group, or a carbon atom with 3 hydrogens being added to the DNA. You can have too many methyl groups (over-methylation) or too few methyl groups (under-methylation). Histones are proteins that help fold the DNA into compact packages and impacts gene activity. For both methylation and histone modifications, you need the Goldilocks effect: not too many, not too few. The body works hard to keep this balance and the body depends on having access to enough nutrients and building blocks to maintain everything “just right.” Methylation and histones can be easily influenced by diet and environment. Some of the most common nutrients that help support methylation are B-vitamins, specifically folate and choline. Biotin, another type of b-vitamin, sulforaphane (a compound from broccoli) and caloric restriction also appear to cause changes to histones, which may help protect the body against certain conditions (2).
Depending where methyl groups are attached or histones are modified, these changes in your DNA can be passed to future generations through the sperm and egg. For example, mothers who smoked while pregnant induced methylation changes in certain parts of the babies’ DNA. These methylation changes were still present even when the children were ~7 years of age (3). In Sweden, researchers discovered that young men who were exposed to famine while their sperm was developing, about 8-9 years of age, had grandsons who lived longer than men who were exposed to “feasting” during the same age (4). In fact, the grandsons of the feasting grandfathers had their life span shortened by 6 years and often developed diabetes (5).
In conclusion, while these small changes to our DNA structure may seem rather harmless, it is vital to realize that cells adapt to their environment and make changes to support the body. More importantly, those changes can be passed onto future generations which may help protect or predispose our future generations to certain conditions.
If you are curious about the status of your body’s ability to methylate, we recommend looking at the folate metabolism section in our Nutrient Optimization panel.
Have additional questions? Email us at info@toolboxgenomics.com
References
(3) DNA Methylation in Newborns and Maternal Smoking in Pregnancy: Genome-wide Consortium Meta-analysis
(4) Kaati et al., “Transgenerational Response to Nutrition, Early Life Circumstances and Longevity.”