Epigenetics Overview

Principles

Definition

Epigenetics is the study of heritable modifications in gene expression or cellular phenotype that do not involve changes to the underlying DNA sequence, investigating the molecular mechanisms (such as DNA methylation and histone modifications) that regulate genome function and their critical roles in development, differentiation, and environmental response.

Ontological type

Key Molecular Mechanisms

Experimental Techniques

Developmental Roles

Key developments

Key Figures

Chromatin and DNA Methylation era

Rudolf Jaenisch [1] emerges as a central figure in the Chromatin and DNA Methylation era, with affiliations at Harvard University [3] and the Massachusetts Institute of Technology [4] during this period. Jaenisch's key contribution in this era is the 1992 paper 'Targeted mutation of the DNA methyltransferase gene results in embryonic lethality' [5], which demonstrated that DNA methylation is essential for embryonic development and transcriptional regulation, providing crucial evidence for methylation as a heritable regulator across cell divisions. Timothy H. Bestor [2] is likewise linked to Harvard University [3] and the Massachusetts Institute of Technology [4] in this era. Bestor's contribution centers on the same 1992 DNA methyltransferase paper [5], illustrating how perturbations in DNA methylation disrupt development and cement the role of DNA methyltransferase in epigenetic regulation, foundational for subsequent locus-specific and genome-wide epigenetic investigations.

Cancer and Chromatin Integration era

James G. Herman[1], affiliated with Johns Hopkins University[3] and the University of Maryland, Baltimore[4], helped shape cancer epigenetics in this era. His key contributions include the development of Methylation-specific PCR[7], Alterations in DNA Methylation: A Fundamental Aspect of Neoplasia[8], and the demonstration of the synergy of demethylation and histone deacetylase inhibition in re-expression of genes silenced in cancer[9], which demonstrated the central role of DNA methylation in oncogenesis during this era. C. David Allis[2], affiliated with Rockefeller University[5] and the University of California, San Francisco[6], propelled the field with the histone code concept in this era. His contributions include The language of covalent histone modifications[10] and the molecular basis for the discrimination of repressive methyl-lysine marks in histone H3 by Polycomb and HP1 chromodomains[11], which clarified how histone marks govern chromatin states in cancer.

High-Resolution Epigenomics era

Bing Ren [1] is associated with Stanford University [3] and the University of Pennsylvania [4] in this era. His key contributions include Integrative analysis of 111 reference human epigenomes [7] and Human DNA methylomes at base resolution show widespread epigenomic differences [8], which established base-resolution methylomes as a basis for cross-tissue comparisons and epigenome-wide characterizations. Joseph R. Ecker [2] has been linked with University of California, San Diego [5] and Icahn School of Medicine at Mount Sinai [6] in this era. His contributions, as demonstrated by Integrative analysis of 111 reference human epigenomes [7] and Human DNA methylomes at base resolution show widespread epigenomic differences [8], advanced large-scale epigenomic mapping and base-resolution methylome profiling, enabling development, aging, and translational epigenetics.