From high school biology, most of us have at least a fuzzy recollection of the DNA spiral that makes up our genes and that our genes determine such things as eye color and hair color. Since those school days, much more has been uncovered, including a flourishing new field of study called epigenetics.
Epigenetics has to do with the factors that influence if genes express themselves. For example, a family line may be known to have heart disease. One person may do things differently than the rest of the family, such as eating a heart-healthy diet, exercising daily, learning stress resilience and taking relaxation time daily. This person’s interventions could be protective so the gene with increased risk of heart disease was never turned on. This is epigenetics at its finest.
We know that environment and lifestyle may influence DNA and impact how our genes express themselves. Lack of sleep, a high sugar diet and poor stress resilience have been linked to changes in our biological sleep patterns, heart health and even tumor growth, respectively. Pharmaceutical companies have even gotten on board in creating epigenetic drugs to treat certain types of cancer.
An interesting and promising arm of epigenetics is the field of study that follows genetic inheritance through generations called transgenerational epigenetic inheritance. Not only can our own lifestyle habits and environmental situations affect our health, but it can affect our offspring in specific ways that scientists are just now beginning to understand and explore. For example, poor nutrition or food scarcity for a grandfather can increase the mortality risk for his grandsons, but not his granddaughters. Conversely, a mother’s good nutrition has been found in some studies to decrease her child’s risk of heart disease.
One study, modeled off of an early human study of the Dutch famine, involving mice said that poor nutrition for a mother increased her offspring’s risk of developing diabetes and becoming obese, as it did the next generation. However, at the third generation the risk factor ended, suggesting that epigenetic changes — in this case starvation — lasted just long enough for our environment to change. In this example it was from famine to feast.
Another study suggested that mothers exposed to pollution during pregnancy had offspring who were at higher risk for asthma all the way into the third generation, although it was weaker risk with the later generations.
This fascinating area of study will certainly offer more information over the years to come as scientific discoveries are made, replicated and verified.