Univariate ROC curves analyses of T-Tau, P-Tau181, Aβ42, Aβ40 concentrations and Aβ42/Aβ40 ratio levels yielded cut-off values for the diagnosis of AD of ≥355, ≥57, ≤706, ≥10,854, and ≤0.059 ng/L, respectively (Figure 1). The gene discussed is MAPT; the disease is Alzheimer disease.