Asthma and epigenetics

ABSTRACT

For the past two decades, a huge number of genetic studies have been conducted to identify the genetic variants responsible for asthma risk. Several types of genetic and genomic approaches, including linkage analysis, candidate gene single nucleotide polymorphism studies, and whole genome-wide association studies have been applied. However, the genetic impacts of these studies are minimal because asthma is a complex syndrome affected by interaction with many environmental factors mediated by epigenetics. Epigenetics is alteration of genetic expression without changes of DNA sequence. Three major forms of epigenetic is DNA methylation, histone modfications and specific microRNA expression that are known to have vast effects on gene expression. However, knowledge regarding the epigenetic effect on the development of asthma and its traits is limited up to date. Recently, new data on epigenetics have been brought up to explain the phenotypic alterations of asthma. In this review, we present general concept of epigenetics, environmental factors inducting epigenetic changes and the background mechanisms in epigenetics behind development asthma and epigenetic therapy.