Approximately 5% of the children studied in our international HSE cohort have experimentally proven AR or AD deficiencies of the TLR3-IFN-α/β circuit, which governs cell-intrinsic immunity in specific organs of the human body, including the brain and the lung (80–82), and another ~2% have AD or AR deficiencies of snoRNA31 or DBR1, which govern new antiviral mechanisms that appear to be specific to the forebrain and brainstem, respectively (33, 34). Here, IFNA2 is linked to Alzheimer disease.