Moreover, adopting tau-PET tracer instead of histopathological staining, heterogeneity in spreading patterns was suggested by a study, comprising limbic-predominant phenotype, parietal-dominant and medial temporal lobe-sparing phenotype, predominant posterior occipitotemporal phenotype, and asymmetric temporoparietal phenotype, which might unify the propagation patterns of typical and atypical AD [89]. The gene discussed is MAPT; the disease is Alzheimer disease.