Epigenetics

DNA sequence is a critical source of information for all biological processes, but the regulation of gene activity is necessary for this genetic potential to be utilized. Epigenetics refers to molecular mechanisms that contribute to the regulation of gene activity, resulting in either increases or decreases in gene expression (transcription). These mechanisms do not involve modifications to the DNA sequence. In 1942, Conrad Waddington coined the term epigenetics to describe the complex interplay between genes and their products, which occur during development to establish the divergence of phenotypes (characteristics) that emerge from a given genotype. An example of the role of epigenetics in development is illustrated by the process of cellular differentiation. An organism has a single genome, and that genome is copied when cells ...