Selecting a biologic involves consideration of the patient’s asthma phenotype and co-morbid atopic conditions [32] such as atopic dermatitis (see Atopic Dermatitis article in this supplement) [3], food allergy (see IgE-mediated Food Allergy paper in this supplement) [33], CRSwNP, chronic urticaria (see Urticaria article in this supplement) [34], and eosinophilic esophagitis (see Eosinophilic Esophagitis article in this supplement) [35]. The gene discussed is IGHE; the disease is atopic eczema.