An epigenetic trait is a stably inherited phenotype resulting from changes in a chromosome
without alterations in the DNA sequence. Epigenetic modifications such as DNA methylation,
together with covalent modification of histones, are thought to alter chromatin density and
accessibility of the DNA to cellular machinery, thereby modulating the transcriptional
potential of the underlying DNA sequence. As environmental changes influence epigenetic
marks, epigenetics provides an added layer of variation that might mediate the relationship …