Asthma and other allergic diseases are among the most prevalent chronic non-communicable diseases of childhood. According to the World Health Organization, asthma affects> 7.0 million children under 18 in the United States, with an economic burden that is estimated to exceed that of tuberculosis and HIV/AIDS combined. Despite much research, the natural history of asthma and its pathogenesis are still in many ways elusive. This review discusses our current understanding of the role epigenetic processes play in asthma pathogenesis, focusing on genome-wide, population-based studies. Copyright© 2015, Japanese Society of Allergology. Production and hosting by Elsevier BV This is an open access article under the CC BY-NC-ND license (http://creativecommons. org/licenses/by-nc-nd/4.0/).