Renard et al. evaluated cerebrospinal fluid amyloid-β 1–40 (Aβ40), amyloid-β 1–42 (Aβ42), total and phosphorylated-tau (t-tau and p-tau) in patients with symptomatic isolated cSS, and found that the patients with cSS showed higher t-tau and lower Aβ42 compared to the controls, and lower t-tau, p-tau, and Aβ40 compared to the AD patients (17). Here, MAPT is linked to Alzheimer disease.