MAPT and Alzheimer disease: Given the relatively superficial location of p-tau in the cortex of patients with CTE compared to AD and the lack of notable involvement of amyloid β in CTE, we hypothesized that CTE participants may have increased t-tau, p-tau181, and p-tau231 compared to cases without either CTE or AD (control), as well as relatively higher p-tau181, p-tau231, and Aβ42 concentrations compared to AD cases.