Introduction to Epigenetics

Abstract In Apr., 2003, the International Human Genome Sequencing Consortium announced the completion of the Human Genome Project. All 3,000,000,000 base pairs of nucleotides had been sequenced, yielding about 30,000 genes in the human genome. At the time, the predominant opinion was that knowing the sequence of the human genome would reveal the origin of all diseases, thereby unveiling information required to understand human health fully. However, substantial phenotypic disparity and disease susceptibility remained that was not explained by DNA sequence alone. Continued research in molecular biology began to focus on the field of epigenetics as a mechanism of interaction between the environment and genome to gain further insight into disease. Epigenetics is an additional layer of genomic modulation that drives the transition from genotype to phenotype by dynamically regulating where and when genes are expressed. At the time of publication, a search for the term “epigenetics” on PubMed yielded over 20,000 articles, highlighting interest in this topic within the field of health sciences.