“…Two recent publications identified elevated DNA methylation level in the promoter regions of interferon (IFN)-and IL-4 in CD4 + T cells of pediatric AR (Li, Mu, Wang, Liu, & Jiang, 2018;Li, Rui, Ma, Jiang, & Chen, 2019), which was further revealed to be regulated via the extracellular signal-regulated kinase-DNA methyltransferase pathway as illustrated in the murine model (Li, Zhou, Rui, Zhou, & Mo, 2019). By comparing DNA methylation profiles in peripheral blood mononuclear cells before and after grass pollen exposure, 42 sites showing a significantly higher level of DNA methylation were discovered, among which three genes were further validated by pyrosequencing, namely TPSG1, SLFN12 and MUC4 (North et al, 2018). Hypomethylation of the IL13 gene was observed, in company with increase expression of IL-13 and serum IgE overloading, which in turn led to higher susceptibility to AR from house dust mite sensitization (Li et al, 2016).…”