Epigenetics and Chronic Diseases: An Overview

Abstract

According to the World Health Organization, chronic diseases account for an estimated 35 million deaths per year, representing ∼60{\%} of worldwide mortality.163 These disorders, including heart disease, obesity, arthritis, cancer, diabetes, psychiatric illness and dementia, confer a major economic, social, and healthcare burden. In the developed world, for example, the treatment of chronic disease accounts for the major proportion of public healthcare spending. As demographic factors shift and the population ages, the prevalence of chronic disease is likely to increase significantly, especially in the developing world. For instance, the prevalence of adult obesity is on a dramatic upward trajectory, increasing from 12{\%} in 1989 to 27{\%} in 2008 in the USA (http://www.cdc.gov/brfss/). Likewise, as the population ages, the number of cases of Alzheimer's Disorder is projected to increase from an estimated 24 million in 2001 to >80 million by 2040, with rates in countries such as India and China increasing by more than 300{\%} over this period.41 The possibility of understanding the biology underpinning human chronic illness is therefore one of the most exciting perspectives of contemporary biomedical research, and the focus of considerable research effort across the world.