Notably, blood-based biomarkers represent a novel tool to identify individuals at an early stage of AD [6]; indeed, in the last few decades, several blood circulating molecules have been investigated as AD diagnostic biomarkers, including AD-related molecules (Aβ, tau and phosphorylated tau), proteins, metabolites, and microRNAs (miRNAs). The gene discussed is MAPT; the disease is Alzheimer disease.