The core blood biomarkers of AD include Aβ42 (or Aβ42/40 ratio), phosphorylated tau181 (p‐tau181), neurofilament light chain (NfL), and total tau (T‐tau), which reflect Aβ pathology, tau pathology, and neuronal damage, respectively.5, 6. This evidence concerns the gene MAPT and Alzheimer disease.