IGHE and Alzheimer disease: Next, clinical and laboratory characterization revealed that the “low IFNG” cluster exhibited features of extrinsic AD with an increased presence of bronchial asthma (28% vs. 14%) and allergic rhino conjunctivitis (52% vs. 43%) (Figure 1G), as well as high serum IgE levels (6937 ± 2443 kU/I vs. 31.9 ± 3.9 kU/I) (Figure 1H) compared to the “high IFNG” cluster.