We found a negative correlation between severity of AD and the abundance of the families Carnobacteriaceae, Gemellaceae, Leptotrichaceae, Micrococcaceae, Neisseriaceae, Porphyromonadaceae, Streptococcaceae, and Weeksellaceae as well as the genera Alloprevotella, Bergeyella, Gemella, Granulicatella, Leptotrichia, Neisseria, Porphyromonas, Rothia, and Streptococcus in AD patients with IgE CMA but not in non-IgE CMA patients (Figure S2). Here, IGHE is linked to Alzheimer disease.