Epigenetics: 1. The study of heritable changes in gene function that occur without a change in the sequence of the DNA. For example:
- The process of DNA methylation; and
- The process of chromatin remodeling.
2. The study of certain processes that occur in embryonic development. For example:
- X inactivation (the inactivation of one X chromosome in females); and
- The phenomenon of gene silencing.