Importantly, while filaggrin expression is almost entirely restricted to the epidermis, FLG mutations have been also shown to be linked to additional manifestations of atopic march and allergy, including food (Brown et al., 2011) and contact allergies (Novak et al., 2008), asthma (van den Oord and Sheikh, 2009; Rodríguez et al., 2009), allergic rhinitis (van den Oord and Sheikh, 2009) and eosinophilic esophagitis (Sherrill and Blanchard, 2014). This evidence concerns the gene FLG and asthma.