In vitro detection of immunoglobulins (Ig) in serum is a widely used strategy for the diagnosis of a multitude of pathologies, from infectious diseases to autoimmune and allergic diseases.[1] In the case of allergy, most in vitro diagnostic techniques are based on the detection of allergen‐specific IgE as the main biomarker.[2] This is because the most common mechanism of activation of an allergic response begins with recognition of the allergen by at least two adjacent IgE molecules that are bound to the high‐affinity receptor (FcεRI) on the cell membrane of mast cells and basophils. The gene discussed is IGHE; the disease is infectious disease.