Plasma p-tau is currently considered the most promising biomarker of brain tau and Aβ pathologies in sporadic and autosomal dominant AD.13 Although the discriminative accuracy of plasma p-tau181 for Aβ-PET status in DS has recently been reported,11 associations between plasma biomarkers and tau-PET have not been studied in this population, and it is also unclear if combinations of different plasma biomarkers offer improved accuracy for identifying individuals with DS who have abnormal tau-PET or Aβ-PET scans. This evidence concerns the gene MAPT and Dravet syndrome.