Epigenetics in allergic diseases

Purpose of review Allergic diseases are among the most prevalent chronic diseases of childhood, affecting more than 7 million children in the United States. Epidemiological evidence supports the idea that the inception of allergic diseases is typically before the preschool years, even when chronic symptoms do not emerge until adulthood. The role of epigenetic mechanisms (particularly DNA methylation) in allergic disease is under active investigation because these mechanisms are known to be at the interface of gene regulation, environmental stimuli, and developmental processes, all of which are essential for the pathogenesis for asthma and allergy. This article specifically reviews genome-wide DNA methylation studies in allergic disease. Recent findings Differential DNA methylation at specific regions appears to be associated with concurrent allergic disease. A few studies have identified methylation signatures predictive of disease. Summary DNA methylation signatures have been shown to be associated with several allergic disease phenotypes, typically concurrently with disease. The few that have been found to precede diagnosis are especially interesting because they highlight an early trajectory to disease.