What is Epigenetics?The prefix 'epi' is derived from the Greek preposition 'nope' meaning: 'above'.In biology, 'Epigenetics' is the study of cellular and physiological trait variations that are not caused by changes in the DNAsequence.Broadly, we can consider them semipermanentchanges that effect a set of gene expression changes; however, theyare reversible.Epigenetic changes are primarily acquired through DNA methylation, which occurs at the cytosine located in a CpG dinucleotide (regions of DNA where a cytosine nucleotide occurs next to a guanine nucleoti de in the linear sequence of bases along its length), and post-translational histone modifications.These chromatin modifications are usually tightly regulated in development and differentiation.(1)