As such, given the need for more accessible Alzheimer’s disease biomarkers, blood-based biomarkers, such as measures of phosphorylated tau, Aβ42/40 ratio and neurofilament light protein,7 constitute a viable promise and warrant thorough investigation with regards to their specificity to Alzheimer’s disease.8 This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.