Plasma t‐tau correlates with cognitive decline in MCI ( Mielke et al., 2017), and plasma p‐tau181 is associated with both Aβ and tau PET (Mielke et al., 2018) and is more closely associated with AD neuropathology than a clinical diagnosis (Lantero Rodriguez et al., 2020). The gene discussed is MAPT; the disease is Alzheimer disease.