Simplify the following text for a Grade 13 native English-speaking person.
Original: In biology , and specifically genetics , epigenetics is the study of heritable changes in phenotype ( appearance ) or gene expression caused by mechanisms other than changes in the underlying DNA sequence , hence the name epi - ( Greek : Î Ï Î - over , above ) - genetics .
Simplified: In biology , the term epigenetics refers to changes in phenotype ( appearance ) or gene expression caused by mechanisms other than changes in the DNA sequence .