In a review by Rial and Domínguez-Ortega, it was noted that some degree of AHR or lung function impairment may be present in patients with asthma without significant symptoms or in those with low or undetectable serum or airway biomarker levels (e.g., FeNO, eosinophils, or allergen-specific immunoglobulin [Ig]E) [44]. The gene discussed is IGHE; the disease is asthma.