IL4 and asthma: These differences in methylation marks are found in genes already previously linked to allergies and IgE levels such as IL4 and IL5 receptor but also novel genes such as LPCAT2 (involved in lysophospholipid metabolism), L2HGDH (a mitochondrial oxidoreductase), and in the transcription factor ZNF22. In this study, patients with established allergies and asthma were investigated at one time point only.