Cryo-EM ultrastructural evaluation of tau fibrils studies show that among tauopathies, CBD, AGD, and ARTAG fibrils have more structural resemblance (four-layered fold), while PSP fibrils are similar to those of GGT (three-layered fold), and PART and AD fibrils are identical (16). The gene discussed is MAPT; the disease is Alzheimer disease.