All of our cells contain the same DNA – a complete blueprint for every cell and process in the body. But not every gene needs to be used in all cells or at all times. Epigenetic markers attach to DNA to modify the way it functions. Small markers called methyl groups bind to DNA and turn off genetic instructions that aren’t needed and allow others to be expressed.
Think of a college textbook. If DNA is all of the letters in the book, then epigenetic markers are the spaces and punctuation between words. They also include the note at the beginning of each chapter alerting a medical student studying for a test on the digestive system that they can skip the chapters on the reproductive system and respiration.
Typically, epigenetic markers are reset from one generation to another. But new research shows that alterations in the pattern of markers for sperm or egg cells can be passed down from one generation to the next.