Like human AD, canine AD is associated with severe pruritus, skin xerosis and increased transepidermal water loss, face and skin fold involvement, spongiotic dermatitis, skin-infiltrating eosinophils, skin infiltration by IgE(+) and CD1c(+) dendritic cells, Th2-dominated immune responses, positive atopy patch test, and IgE-specific responses. Here, IGHE is linked to Alzheimer disease.