CSF sPDGFRβ correlated strongly with t‐tau (r = 0.75, p < 0.0001) and p‐tau (r = 0.70, p < 0.0001) in MCI and strongly with Aβ1‐40 (r = 0.76, p < 0.0001) and Aβ1‐42 (r = 0.58, p = 0.002), in addition to t‐tau (r = 0.54, p = 0.01) and p‐tau (r = 0.42, p = 0.04), in AD. This evidence concerns the gene MAPT and Alzheimer disease.