Recent evidence indicates that phosphorylated tau can spread by “seeding” between interconnected neurons, with the ERC a likely origin early in disease,10, 14, 15, 16, 17 a finding that has been replicated in rodent AD models.17, 18, 19, 20, 21, 22, 23, 24, 25. The gene discussed is MAPT; the disease is Alzheimer disease.