MAPT and Alzheimer disease: Traditional methods to diagnose AD most often involve a clinical judgement made by weighing data derived from some combination of patient history, a wide variety of simple or more extensive neuropsychological screeners and tests, diagnostic imaging, and cerebrospinal fluid (CSF) analyses of various biomarkers, such as Aβ42 and Aβ40, total tau, and various forms of phosphorylated tau (pTau) [13–22].