In the multicentre cohort, serum p-tau 181 levels were higher in patients with AD (n = 111) and ALS (n = 152) compared to disease controls (n = 99, both p < 0.001) with no differences between patients with AD and ALS (Table 1, Fig. 1A, Supplementary Fig. 2). This evidence concerns the gene MAPT and Alzheimer disease.