Epigenetics, the study of heritable, reversible changes in gene function that do not result from altering the underlying gene sequence, has gained significant attention over the past decade. Author Lyle Armstrong has written a detailed yet properly accessible text meant to provide higher-level undergraduate or graduate students with the necessary basics of epigenetics. Before getting started on more in depth epigenetic studies, this text can serve as a launch pad for the student, preparing him with the fundamental tools before he approaches his projects. Armstrong’s objective was not only to communicate the basics of epigenetics, but to simultaneously connect these facts with the effects of epigenetics on cell functions, which is apparent in the flow of text. The bulk of the text starts with the basics of chromatin architecture and remodeling, proceeds through the basic epigenetic processes of DNA methylation and histone modifications, and eventually leads into the epigenetic control of cellular function. This latter section explores the various ways epigenetics is involved in cell division, genomic imprinting, and the pluripotency of embryonic stem cells.
All of the valuable information the student acquires in the preceding chapters prepares him for the final three chapters discussing the epigenetic basis of disease, including imprinting-based disorders, diabetes, neurodegenerative and mental health disorders, and, finally, cancer. There are more than 100 documented forms of cancer responsible for approximately 1.6 newly diagnosed cases and 600,000 deaths in 2012 alone. It is well understood that cancer results from the proliferation and clustering of abnormal cells to produce tumors that ultimately disrupt normal cell function. This chapter investigates the ways that cancer interferes with epigenetic processes to result in tumorgenesis. Armstrong considers a handful of epigenetic glitches, including DNA hyper- or hypomethylation affecting cellular redox status and a malfunction in the histone acetylation/deacetylation balance. With the expected burgeoning of cancer rates over the coming decade, it is imperative to investigate potential treatments. Therapies affecting epigenetic mechanisms could be one fruitful route.