Treatment of AD transgenic mice with AAVECD‐Fc administered either in one of the lateral ventricles or peripherally improved learning and memory and reduced AD pathologies, including amyloid plaques, tau phosphorylation, cell death, synaptic degeneration, and neuroinflammation (Yao et al. 2015; Wang et al. 2016). The gene discussed is MAPT; the disease is Alzheimer disease.