Semantics Question: epigenetic mark on a person's DNA? In an article on biomarkers of child abuse, the author referred to an "epigenetic mark on a person's DNA". It's a popular science article, so the language may reflect a combination of the journalist's scientific competency and his or her desire to communicate complex topics efficiently to a lay audience. Is that an example of such language? My understanding was that anything in the realm of "epigenetics" is happening to something other than DNA. Is it technically correct to refer to an "epigenetic mark on a person's DNA"? Correct enough? Only potentially misleading? I'm trying to wrap my head around the whole epigenetics concept.

We may restrict your definition of epigenetics as heritable changes in an organism's phenotype that occur without a change in the _sequence of DNA bases_. That is, changes to the DNA molecule itself is permitted, as long as the sequence of ATCGs are not affected.

In this sense, it would not be wrong to refer to an "epigenetic mark on a person's DNA". For example, a mechanism of epigenetics that does directly change the DNA molecule would be something like DNA methylation.