We are the first to show the higher CG methylation content of the LMO2 or IL10 is correlated to prenatal exposure of PTS, and the combination of LMO2_E148 (≧28.5%), IL10_P325 (≧38.5%), and GSTM1_P266 (≧41.5%) reveals the highest risk to childhood asthma. Here, GSTM1 is linked to asthma.