We often think of our genetic code as the primary determinant of our health, personality, and experience. While our genes provide an intricate groundwork for everything that we are, simply existing as a template is not enough to create the diversity in human experience that we are all familiar with. In all actuality, our genetics act similarly to american government. In the United States, there are federal laws that apply to all states, this is our genetic code. However, for those of you who are familiar with the US, you know that each state, each separate “environment,” has its own set of guidelines for following these federal laws.
In reality, what matters are what laws are imposed by your specific environment. In terms of our genetic code, we call these environmental-based modifications “epigenetic modifications.” These are modifications made to the DNA, due to environmental pressures, to modify how and which genes are actively expressed. Each human cell (not including sperm and eggs) has enough DNA to stretch out linearly for 2 meters. Considering how we have almost 40 trillion cells in our body, the total amount of DNA would stretch for tens of millions of kilometers (Alberts et al., 2018; Roy & Conroy, 2018)! In order to fit all of this DNA inside our body it has to be tightly coiled.
The coiling of the DNA makes it good for storage, but impossible for the body to use. Therefore, small portions of the DNA are uncoiled and read at a time in order to create proteins in your body (Lind & Spagopoulou, 2018). This is where epigenetic modifications come into play. Environmental stressors, cause your body to release hormones and other signaling molecules that modify the coiling of your DNA. This can silence some genes, while overexpressing others (Weinhold, 2006; Deans & Maggert, 2015). So while the original code is not changed, the portions that are read are different.
Epigenomic studies are key in understanding how the world we live in shapes our own internal world. Through continued research, scientists are beginning to show that different psychiatric disorders are associated with specific epigenetic patterns (especially in BD, Schizophrenia, Alzheimer’s disease, and ASD) (Abel & Poplawski, 2014). By better understanding this interplay scientists are working to develop drugs to combat specific epigenetic proteins in order to prevent the negatives of epigenetic modifications, while preserving the benefits. As our technology gets better and better, there is hope that we can one day modify our epigenome in the same way that we amend harmful laws.