These plaques are composed primarily of amyloid‐β peptides (Aβ), which is a cleavage product after processing of the amyloid precursor protein (APP) that consists of 36–43 amino acids.1 Positron emission tomography (PET) is employed to visualize amyloid deposits in vivo, enabling a non‐invasive diagnosis of AD. The gene discussed is APP; the disease is Alzheimer disease.