The performance of p‐tau181 in differentiating LBD from MCI+/AD, and LBD PET Aβ− from LBD PET Aβ+ in this sample, may relate to the age and disease stage of the LBD group, variation in the definition of AD co‐pathology and plasma p‐tau assays between studies, and potential clinical misdiagnosis (although clinical consensus criteria provide high sensitivity and specificity for the diagnosis of DLB66). The gene discussed is MAPT; the disease is Alzheimer disease.