Epigenetics

Epigenetics refers to changes to a gene's activity, expression, and/or regulation that do not involve changes to the DNA sequence. This concept is important because it implies that lifestyle or environmental factors may influence whether certain genes with harmful potential express or not. Thus, possessing a gene associated with a disease does not always mean that a person will show symptoms of that disease.

It is possible for epigenetic changes to pass from one generation to the next.