Figure 2
From: Towards identification of molecular mechanisms of short stature
The epigenetic context of gene regulatory elements can dictate gene expression. Active and inactive gene promoters are distinguished by several epigenetic features including chromatin accessibility, DNA methylation, covalent modification of histone tails, and the types of transcriptional proteins in the vicinity. These epigenetic features are frequently dichotomous in the same gene in different tissues, and also may be different in the same gene within the same tissue of different individuals as an explanation for differences in gene profiles. By definition, epigenetic changes do not involve any differences in the underlying DNA sequence.