We aimed to determine the prevalence of the eosinophilic (defined in this study as ≥ 300 cells/mm3 in blood), atopic (atopic phenotype 1, defined in this study as > 100 IU/mL total serum IgE; atopic phenotype 2, defined in this study as > 150 IU/mL), and overlap phenotypes among patients with severe asthma in Saudi Arabia. The gene discussed is IGHE; the disease is asthma.