In this study, we set out to answer this question by first of all ascertaining whether there are hyperphosphorylated tau aggregates in cortical and striatal tissues from patients with Huntington’s disease, with comparison to cases with a known tauopathy (Alzheimer’s disease, progressive supranuclear palsy, Pick’s disease and corticobasal degeneration) and healthy control subjects. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.